Index: frontend/node_modules/decimal.js/decimal.mjs =================================================================== --- frontend/node_modules/decimal.js/decimal.mjs (revision 9af201e94b5a79beb92a30858fc54de4bc3b9449) +++ frontend/node_modules/decimal.js/decimal.mjs (revision 9af201e94b5a79beb92a30858fc54de4bc3b9449) @@ -0,0 +1,4914 @@ +/*! + * decimal.js v10.6.0 + * An arbitrary-precision Decimal type for JavaScript. + * https://github.com/MikeMcl/decimal.js + * Copyright (c) 2025 Michael Mclaughlin + * MIT Licence + */ + + +// ----------------------------------- EDITABLE DEFAULTS ------------------------------------ // + + + // The maximum exponent magnitude. + // The limit on the value of `toExpNeg`, `toExpPos`, `minE` and `maxE`. +var EXP_LIMIT = 9e15, // 0 to 9e15 + + // The limit on the value of `precision`, and on the value of the first argument to + // `toDecimalPlaces`, `toExponential`, `toFixed`, `toPrecision` and `toSignificantDigits`. + MAX_DIGITS = 1e9, // 0 to 1e9 + + // Base conversion alphabet. + NUMERALS = '0123456789abcdef', + + // The natural logarithm of 10 (1025 digits). + LN10 = '2.3025850929940456840179914546843642076011014886287729760333279009675726096773524802359972050895982983419677840422862486334095254650828067566662873690987816894829072083255546808437998948262331985283935053089653777326288461633662222876982198867465436674744042432743651550489343149393914796194044002221051017141748003688084012647080685567743216228355220114804663715659121373450747856947683463616792101806445070648000277502684916746550586856935673420670581136429224554405758925724208241314695689016758940256776311356919292033376587141660230105703089634572075440370847469940168269282808481184289314848524948644871927809676271275775397027668605952496716674183485704422507197965004714951050492214776567636938662976979522110718264549734772662425709429322582798502585509785265383207606726317164309505995087807523710333101197857547331541421808427543863591778117054309827482385045648019095610299291824318237525357709750539565187697510374970888692180205189339507238539205144634197265287286965110862571492198849978748873771345686209167058', + + // Pi (1025 digits). + PI = '3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461284756482337867831652712019091456485669234603486104543266482133936072602491412737245870066063155881748815209209628292540917153643678925903600113305305488204665213841469519415116094330572703657595919530921861173819326117931051185480744623799627495673518857527248912279381830119491298336733624406566430860213949463952247371907021798609437027705392171762931767523846748184676694051320005681271452635608277857713427577896091736371787214684409012249534301465495853710507922796892589235420199561121290219608640344181598136297747713099605187072113499999983729780499510597317328160963185950244594553469083026425223082533446850352619311881710100031378387528865875332083814206171776691473035982534904287554687311595628638823537875937519577818577805321712268066130019278766111959092164201989380952572010654858632789', + + + // The initial configuration properties of the Decimal constructor. + DEFAULTS = { + + // These values must be integers within the stated ranges (inclusive). + // Most of these values can be changed at run-time using the `Decimal.config` method. + + // The maximum number of significant digits of the result of a calculation or base conversion. + // E.g. `Decimal.config({ precision: 20 });` + precision: 20, // 1 to MAX_DIGITS + + // The rounding mode used when rounding to `precision`. + // + // ROUND_UP 0 Away from zero. + // ROUND_DOWN 1 Towards zero. + // ROUND_CEIL 2 Towards +Infinity. + // ROUND_FLOOR 3 Towards -Infinity. + // ROUND_HALF_UP 4 Towards nearest neighbour. If equidistant, up. + // ROUND_HALF_DOWN 5 Towards nearest neighbour. If equidistant, down. + // ROUND_HALF_EVEN 6 Towards nearest neighbour. If equidistant, towards even neighbour. + // ROUND_HALF_CEIL 7 Towards nearest neighbour. If equidistant, towards +Infinity. + // ROUND_HALF_FLOOR 8 Towards nearest neighbour. If equidistant, towards -Infinity. + // + // E.g. + // `Decimal.rounding = 4;` + // `Decimal.rounding = Decimal.ROUND_HALF_UP;` + rounding: 4, // 0 to 8 + + // The modulo mode used when calculating the modulus: a mod n. + // The quotient (q = a / n) is calculated according to the corresponding rounding mode. + // The remainder (r) is calculated as: r = a - n * q. + // + // UP 0 The remainder is positive if the dividend is negative, else is negative. + // DOWN 1 The remainder has the same sign as the dividend (JavaScript %). + // FLOOR 3 The remainder has the same sign as the divisor (Python %). + // HALF_EVEN 6 The IEEE 754 remainder function. + // EUCLID 9 Euclidian division. q = sign(n) * floor(a / abs(n)). Always positive. + // + // Truncated division (1), floored division (3), the IEEE 754 remainder (6), and Euclidian + // division (9) are commonly used for the modulus operation. The other rounding modes can also + // be used, but they may not give useful results. + modulo: 1, // 0 to 9 + + // The exponent value at and beneath which `toString` returns exponential notation. + // JavaScript numbers: -7 + toExpNeg: -7, // 0 to -EXP_LIMIT + + // The exponent value at and above which `toString` returns exponential notation. + // JavaScript numbers: 21 + toExpPos: 21, // 0 to EXP_LIMIT + + // The minimum exponent value, beneath which underflow to zero occurs. + // JavaScript numbers: -324 (5e-324) + minE: -EXP_LIMIT, // -1 to -EXP_LIMIT + + // The maximum exponent value, above which overflow to Infinity occurs. + // JavaScript numbers: 308 (1.7976931348623157e+308) + maxE: EXP_LIMIT, // 1 to EXP_LIMIT + + // Whether to use cryptographically-secure random number generation, if available. + crypto: false // true/false + }, + + +// ----------------------------------- END OF EDITABLE DEFAULTS ------------------------------- // + + + inexact, quadrant, + external = true, + + decimalError = '[DecimalError] ', + invalidArgument = decimalError + 'Invalid argument: ', + precisionLimitExceeded = decimalError + 'Precision limit exceeded', + cryptoUnavailable = decimalError + 'crypto unavailable', + tag = '[object Decimal]', + + mathfloor = Math.floor, + mathpow = Math.pow, + + isBinary = /^0b([01]+(\.[01]*)?|\.[01]+)(p[+-]?\d+)?$/i, + isHex = /^0x([0-9a-f]+(\.[0-9a-f]*)?|\.[0-9a-f]+)(p[+-]?\d+)?$/i, + isOctal = /^0o([0-7]+(\.[0-7]*)?|\.[0-7]+)(p[+-]?\d+)?$/i, + isDecimal = /^(\d+(\.\d*)?|\.\d+)(e[+-]?\d+)?$/i, + + BASE = 1e7, + LOG_BASE = 7, + MAX_SAFE_INTEGER = 9007199254740991, + + LN10_PRECISION = LN10.length - 1, + PI_PRECISION = PI.length - 1, + + // Decimal.prototype object + P = { toStringTag: tag }; + + +// Decimal prototype methods + + +/* + * absoluteValue abs + * ceil + * clampedTo clamp + * comparedTo cmp + * cosine cos + * cubeRoot cbrt + * decimalPlaces dp + * dividedBy div + * dividedToIntegerBy divToInt + * equals eq + * floor + * greaterThan gt + * greaterThanOrEqualTo gte + * hyperbolicCosine cosh + * hyperbolicSine sinh + * hyperbolicTangent tanh + * inverseCosine acos + * inverseHyperbolicCosine acosh + * inverseHyperbolicSine asinh + * inverseHyperbolicTangent atanh + * inverseSine asin + * inverseTangent atan + * isFinite + * isInteger isInt + * isNaN + * isNegative isNeg + * isPositive isPos + * isZero + * lessThan lt + * lessThanOrEqualTo lte + * logarithm log + * [maximum] [max] + * [minimum] [min] + * minus sub + * modulo mod + * naturalExponential exp + * naturalLogarithm ln + * negated neg + * plus add + * precision sd + * round + * sine sin + * squareRoot sqrt + * tangent tan + * times mul + * toBinary + * toDecimalPlaces toDP + * toExponential + * toFixed + * toFraction + * toHexadecimal toHex + * toNearest + * toNumber + * toOctal + * toPower pow + * toPrecision + * toSignificantDigits toSD + * toString + * truncated trunc + * valueOf toJSON + */ + + +/* + * Return a new Decimal whose value is the absolute value of this Decimal. + * + */ +P.absoluteValue = P.abs = function () { + var x = new this.constructor(this); + if (x.s < 0) x.s = 1; + return finalise(x); +}; + + +/* + * Return a new Decimal whose value is the value of this Decimal rounded to a whole number in the + * direction of positive Infinity. + * + */ +P.ceil = function () { + return finalise(new this.constructor(this), this.e + 1, 2); +}; + + +/* + * Return a new Decimal whose value is the value of this Decimal clamped to the range + * delineated by `min` and `max`. + * + * min {number|string|bigint|Decimal} + * max {number|string|bigint|Decimal} + * + */ +P.clampedTo = P.clamp = function (min, max) { + var k, + x = this, + Ctor = x.constructor; + min = new Ctor(min); + max = new Ctor(max); + if (!min.s || !max.s) return new Ctor(NaN); + if (min.gt(max)) throw Error(invalidArgument + max); + k = x.cmp(min); + return k < 0 ? min : x.cmp(max) > 0 ? max : new Ctor(x); +}; + + +/* + * Return + * 1 if the value of this Decimal is greater than the value of `y`, + * -1 if the value of this Decimal is less than the value of `y`, + * 0 if they have the same value, + * NaN if the value of either Decimal is NaN. + * + */ +P.comparedTo = P.cmp = function (y) { + var i, j, xdL, ydL, + x = this, + xd = x.d, + yd = (y = new x.constructor(y)).d, + xs = x.s, + ys = y.s; + + // Either NaN or ±Infinity? + if (!xd || !yd) { + return !xs || !ys ? NaN : xs !== ys ? xs : xd === yd ? 0 : !xd ^ xs < 0 ? 1 : -1; + } + + // Either zero? + if (!xd[0] || !yd[0]) return xd[0] ? xs : yd[0] ? -ys : 0; + + // Signs differ? + if (xs !== ys) return xs; + + // Compare exponents. + if (x.e !== y.e) return x.e > y.e ^ xs < 0 ? 1 : -1; + + xdL = xd.length; + ydL = yd.length; + + // Compare digit by digit. + for (i = 0, j = xdL < ydL ? xdL : ydL; i < j; ++i) { + if (xd[i] !== yd[i]) return xd[i] > yd[i] ^ xs < 0 ? 1 : -1; + } + + // Compare lengths. + return xdL === ydL ? 0 : xdL > ydL ^ xs < 0 ? 1 : -1; +}; + + +/* + * Return a new Decimal whose value is the cosine of the value in radians of this Decimal. + * + * Domain: [-Infinity, Infinity] + * Range: [-1, 1] + * + * cos(0) = 1 + * cos(-0) = 1 + * cos(Infinity) = NaN + * cos(-Infinity) = NaN + * cos(NaN) = NaN + * + */ +P.cosine = P.cos = function () { + var pr, rm, + x = this, + Ctor = x.constructor; + + if (!x.d) return new Ctor(NaN); + + // cos(0) = cos(-0) = 1 + if (!x.d[0]) return new Ctor(1); + + pr = Ctor.precision; + rm = Ctor.rounding; + Ctor.precision = pr + Math.max(x.e, x.sd()) + LOG_BASE; + Ctor.rounding = 1; + + x = cosine(Ctor, toLessThanHalfPi(Ctor, x)); + + Ctor.precision = pr; + Ctor.rounding = rm; + + return finalise(quadrant == 2 || quadrant == 3 ? x.neg() : x, pr, rm, true); +}; + + +/* + * + * Return a new Decimal whose value is the cube root of the value of this Decimal, rounded to + * `precision` significant digits using rounding mode `rounding`. + * + * cbrt(0) = 0 + * cbrt(-0) = -0 + * cbrt(1) = 1 + * cbrt(-1) = -1 + * cbrt(N) = N + * cbrt(-I) = -I + * cbrt(I) = I + * + * Math.cbrt(x) = (x < 0 ? -Math.pow(-x, 1/3) : Math.pow(x, 1/3)) + * + */ +P.cubeRoot = P.cbrt = function () { + var e, m, n, r, rep, s, sd, t, t3, t3plusx, + x = this, + Ctor = x.constructor; + + if (!x.isFinite() || x.isZero()) return new Ctor(x); + external = false; + + // Initial estimate. + s = x.s * mathpow(x.s * x, 1 / 3); + + // Math.cbrt underflow/overflow? + // Pass x to Math.pow as integer, then adjust the exponent of the result. + if (!s || Math.abs(s) == 1 / 0) { + n = digitsToString(x.d); + e = x.e; + + // Adjust n exponent so it is a multiple of 3 away from x exponent. + if (s = (e - n.length + 1) % 3) n += (s == 1 || s == -2 ? '0' : '00'); + s = mathpow(n, 1 / 3); + + // Rarely, e may be one less than the result exponent value. + e = mathfloor((e + 1) / 3) - (e % 3 == (e < 0 ? -1 : 2)); + + if (s == 1 / 0) { + n = '5e' + e; + } else { + n = s.toExponential(); + n = n.slice(0, n.indexOf('e') + 1) + e; + } + + r = new Ctor(n); + r.s = x.s; + } else { + r = new Ctor(s.toString()); + } + + sd = (e = Ctor.precision) + 3; + + // Halley's method. + // TODO? Compare Newton's method. + for (;;) { + t = r; + t3 = t.times(t).times(t); + t3plusx = t3.plus(x); + r = divide(t3plusx.plus(x).times(t), t3plusx.plus(t3), sd + 2, 1); + + // TODO? Replace with for-loop and checkRoundingDigits. + if (digitsToString(t.d).slice(0, sd) === (n = digitsToString(r.d)).slice(0, sd)) { + n = n.slice(sd - 3, sd + 1); + + // The 4th rounding digit may be in error by -1 so if the 4 rounding digits are 9999 or 4999 + // , i.e. approaching a rounding boundary, continue the iteration. + if (n == '9999' || !rep && n == '4999') { + + // On the first iteration only, check to see if rounding up gives the exact result as the + // nines may infinitely repeat. + if (!rep) { + finalise(t, e + 1, 0); + + if (t.times(t).times(t).eq(x)) { + r = t; + break; + } + } + + sd += 4; + rep = 1; + } else { + + // If the rounding digits are null, 0{0,4} or 50{0,3}, check for an exact result. + // If not, then there are further digits and m will be truthy. + if (!+n || !+n.slice(1) && n.charAt(0) == '5') { + + // Truncate to the first rounding digit. + finalise(r, e + 1, 1); + m = !r.times(r).times(r).eq(x); + } + + break; + } + } + } + + external = true; + + return finalise(r, e, Ctor.rounding, m); +}; + + +/* + * Return the number of decimal places of the value of this Decimal. + * + */ +P.decimalPlaces = P.dp = function () { + var w, + d = this.d, + n = NaN; + + if (d) { + w = d.length - 1; + n = (w - mathfloor(this.e / LOG_BASE)) * LOG_BASE; + + // Subtract the number of trailing zeros of the last word. + w = d[w]; + if (w) for (; w % 10 == 0; w /= 10) n--; + if (n < 0) n = 0; + } + + return n; +}; + + +/* + * n / 0 = I + * n / N = N + * n / I = 0 + * 0 / n = 0 + * 0 / 0 = N + * 0 / N = N + * 0 / I = 0 + * N / n = N + * N / 0 = N + * N / N = N + * N / I = N + * I / n = I + * I / 0 = I + * I / N = N + * I / I = N + * + * Return a new Decimal whose value is the value of this Decimal divided by `y`, rounded to + * `precision` significant digits using rounding mode `rounding`. + * + */ +P.dividedBy = P.div = function (y) { + return divide(this, new this.constructor(y)); +}; + + +/* + * Return a new Decimal whose value is the integer part of dividing the value of this Decimal + * by the value of `y`, rounded to `precision` significant digits using rounding mode `rounding`. + * + */ +P.dividedToIntegerBy = P.divToInt = function (y) { + var x = this, + Ctor = x.constructor; + return finalise(divide(x, new Ctor(y), 0, 1, 1), Ctor.precision, Ctor.rounding); +}; + + +/* + * Return true if the value of this Decimal is equal to the value of `y`, otherwise return false. + * + */ +P.equals = P.eq = function (y) { + return this.cmp(y) === 0; +}; + + +/* + * Return a new Decimal whose value is the value of this Decimal rounded to a whole number in the + * direction of negative Infinity. + * + */ +P.floor = function () { + return finalise(new this.constructor(this), this.e + 1, 3); +}; + + +/* + * Return true if the value of this Decimal is greater than the value of `y`, otherwise return + * false. + * + */ +P.greaterThan = P.gt = function (y) { + return this.cmp(y) > 0; +}; + + +/* + * Return true if the value of this Decimal is greater than or equal to the value of `y`, + * otherwise return false. + * + */ +P.greaterThanOrEqualTo = P.gte = function (y) { + var k = this.cmp(y); + return k == 1 || k === 0; +}; + + +/* + * Return a new Decimal whose value is the hyperbolic cosine of the value in radians of this + * Decimal. + * + * Domain: [-Infinity, Infinity] + * Range: [1, Infinity] + * + * cosh(x) = 1 + x^2/2! + x^4/4! + x^6/6! + ... + * + * cosh(0) = 1 + * cosh(-0) = 1 + * cosh(Infinity) = Infinity + * cosh(-Infinity) = Infinity + * cosh(NaN) = NaN + * + * x time taken (ms) result + * 1000 9 9.8503555700852349694e+433 + * 10000 25 4.4034091128314607936e+4342 + * 100000 171 1.4033316802130615897e+43429 + * 1000000 3817 1.5166076984010437725e+434294 + * 10000000 abandoned after 2 minute wait + * + * TODO? Compare performance of cosh(x) = 0.5 * (exp(x) + exp(-x)) + * + */ +P.hyperbolicCosine = P.cosh = function () { + var k, n, pr, rm, len, + x = this, + Ctor = x.constructor, + one = new Ctor(1); + + if (!x.isFinite()) return new Ctor(x.s ? 1 / 0 : NaN); + if (x.isZero()) return one; + + pr = Ctor.precision; + rm = Ctor.rounding; + Ctor.precision = pr + Math.max(x.e, x.sd()) + 4; + Ctor.rounding = 1; + len = x.d.length; + + // Argument reduction: cos(4x) = 1 - 8cos^2(x) + 8cos^4(x) + 1 + // i.e. cos(x) = 1 - cos^2(x/4)(8 - 8cos^2(x/4)) + + // Estimate the optimum number of times to use the argument reduction. + // TODO? Estimation reused from cosine() and may not be optimal here. + if (len < 32) { + k = Math.ceil(len / 3); + n = (1 / tinyPow(4, k)).toString(); + } else { + k = 16; + n = '2.3283064365386962890625e-10'; + } + + x = taylorSeries(Ctor, 1, x.times(n), new Ctor(1), true); + + // Reverse argument reduction + var cosh2_x, + i = k, + d8 = new Ctor(8); + for (; i--;) { + cosh2_x = x.times(x); + x = one.minus(cosh2_x.times(d8.minus(cosh2_x.times(d8)))); + } + + return finalise(x, Ctor.precision = pr, Ctor.rounding = rm, true); +}; + + +/* + * Return a new Decimal whose value is the hyperbolic sine of the value in radians of this + * Decimal. + * + * Domain: [-Infinity, Infinity] + * Range: [-Infinity, Infinity] + * + * sinh(x) = x + x^3/3! + x^5/5! + x^7/7! + ... + * + * sinh(0) = 0 + * sinh(-0) = -0 + * sinh(Infinity) = Infinity + * sinh(-Infinity) = -Infinity + * sinh(NaN) = NaN + * + * x time taken (ms) + * 10 2 ms + * 100 5 ms + * 1000 14 ms + * 10000 82 ms + * 100000 886 ms 1.4033316802130615897e+43429 + * 200000 2613 ms + * 300000 5407 ms + * 400000 8824 ms + * 500000 13026 ms 8.7080643612718084129e+217146 + * 1000000 48543 ms + * + * TODO? Compare performance of sinh(x) = 0.5 * (exp(x) - exp(-x)) + * + */ +P.hyperbolicSine = P.sinh = function () { + var k, pr, rm, len, + x = this, + Ctor = x.constructor; + + if (!x.isFinite() || x.isZero()) return new Ctor(x); + + pr = Ctor.precision; + rm = Ctor.rounding; + Ctor.precision = pr + Math.max(x.e, x.sd()) + 4; + Ctor.rounding = 1; + len = x.d.length; + + if (len < 3) { + x = taylorSeries(Ctor, 2, x, x, true); + } else { + + // Alternative argument reduction: sinh(3x) = sinh(x)(3 + 4sinh^2(x)) + // i.e. sinh(x) = sinh(x/3)(3 + 4sinh^2(x/3)) + // 3 multiplications and 1 addition + + // Argument reduction: sinh(5x) = sinh(x)(5 + sinh^2(x)(20 + 16sinh^2(x))) + // i.e. sinh(x) = sinh(x/5)(5 + sinh^2(x/5)(20 + 16sinh^2(x/5))) + // 4 multiplications and 2 additions + + // Estimate the optimum number of times to use the argument reduction. + k = 1.4 * Math.sqrt(len); + k = k > 16 ? 16 : k | 0; + + x = x.times(1 / tinyPow(5, k)); + x = taylorSeries(Ctor, 2, x, x, true); + + // Reverse argument reduction + var sinh2_x, + d5 = new Ctor(5), + d16 = new Ctor(16), + d20 = new Ctor(20); + for (; k--;) { + sinh2_x = x.times(x); + x = x.times(d5.plus(sinh2_x.times(d16.times(sinh2_x).plus(d20)))); + } + } + + Ctor.precision = pr; + Ctor.rounding = rm; + + return finalise(x, pr, rm, true); +}; + + +/* + * Return a new Decimal whose value is the hyperbolic tangent of the value in radians of this + * Decimal. + * + * Domain: [-Infinity, Infinity] + * Range: [-1, 1] + * + * tanh(x) = sinh(x) / cosh(x) + * + * tanh(0) = 0 + * tanh(-0) = -0 + * tanh(Infinity) = 1 + * tanh(-Infinity) = -1 + * tanh(NaN) = NaN + * + */ +P.hyperbolicTangent = P.tanh = function () { + var pr, rm, + x = this, + Ctor = x.constructor; + + if (!x.isFinite()) return new Ctor(x.s); + if (x.isZero()) return new Ctor(x); + + pr = Ctor.precision; + rm = Ctor.rounding; + Ctor.precision = pr + 7; + Ctor.rounding = 1; + + return divide(x.sinh(), x.cosh(), Ctor.precision = pr, Ctor.rounding = rm); +}; + + +/* + * Return a new Decimal whose value is the arccosine (inverse cosine) in radians of the value of + * this Decimal. + * + * Domain: [-1, 1] + * Range: [0, pi] + * + * acos(x) = pi/2 - asin(x) + * + * acos(0) = pi/2 + * acos(-0) = pi/2 + * acos(1) = 0 + * acos(-1) = pi + * acos(1/2) = pi/3 + * acos(-1/2) = 2*pi/3 + * acos(|x| > 1) = NaN + * acos(NaN) = NaN + * + */ +P.inverseCosine = P.acos = function () { + var x = this, + Ctor = x.constructor, + k = x.abs().cmp(1), + pr = Ctor.precision, + rm = Ctor.rounding; + + if (k !== -1) { + return k === 0 + // |x| is 1 + ? x.isNeg() ? getPi(Ctor, pr, rm) : new Ctor(0) + // |x| > 1 or x is NaN + : new Ctor(NaN); + } + + if (x.isZero()) return getPi(Ctor, pr + 4, rm).times(0.5); + + // TODO? Special case acos(0.5) = pi/3 and acos(-0.5) = 2*pi/3 + + Ctor.precision = pr + 6; + Ctor.rounding = 1; + + // See https://github.com/MikeMcl/decimal.js/pull/217 + x = new Ctor(1).minus(x).div(x.plus(1)).sqrt().atan(); + + Ctor.precision = pr; + Ctor.rounding = rm; + + return x.times(2); +}; + + +/* + * Return a new Decimal whose value is the inverse of the hyperbolic cosine in radians of the + * value of this Decimal. + * + * Domain: [1, Infinity] + * Range: [0, Infinity] + * + * acosh(x) = ln(x + sqrt(x^2 - 1)) + * + * acosh(x < 1) = NaN + * acosh(NaN) = NaN + * acosh(Infinity) = Infinity + * acosh(-Infinity) = NaN + * acosh(0) = NaN + * acosh(-0) = NaN + * acosh(1) = 0 + * acosh(-1) = NaN + * + */ +P.inverseHyperbolicCosine = P.acosh = function () { + var pr, rm, + x = this, + Ctor = x.constructor; + + if (x.lte(1)) return new Ctor(x.eq(1) ? 0 : NaN); + if (!x.isFinite()) return new Ctor(x); + + pr = Ctor.precision; + rm = Ctor.rounding; + Ctor.precision = pr + Math.max(Math.abs(x.e), x.sd()) + 4; + Ctor.rounding = 1; + external = false; + + x = x.times(x).minus(1).sqrt().plus(x); + + external = true; + Ctor.precision = pr; + Ctor.rounding = rm; + + return x.ln(); +}; + + +/* + * Return a new Decimal whose value is the inverse of the hyperbolic sine in radians of the value + * of this Decimal. + * + * Domain: [-Infinity, Infinity] + * Range: [-Infinity, Infinity] + * + * asinh(x) = ln(x + sqrt(x^2 + 1)) + * + * asinh(NaN) = NaN + * asinh(Infinity) = Infinity + * asinh(-Infinity) = -Infinity + * asinh(0) = 0 + * asinh(-0) = -0 + * + */ +P.inverseHyperbolicSine = P.asinh = function () { + var pr, rm, + x = this, + Ctor = x.constructor; + + if (!x.isFinite() || x.isZero()) return new Ctor(x); + + pr = Ctor.precision; + rm = Ctor.rounding; + Ctor.precision = pr + 2 * Math.max(Math.abs(x.e), x.sd()) + 6; + Ctor.rounding = 1; + external = false; + + x = x.times(x).plus(1).sqrt().plus(x); + + external = true; + Ctor.precision = pr; + Ctor.rounding = rm; + + return x.ln(); +}; + + +/* + * Return a new Decimal whose value is the inverse of the hyperbolic tangent in radians of the + * value of this Decimal. + * + * Domain: [-1, 1] + * Range: [-Infinity, Infinity] + * + * atanh(x) = 0.5 * ln((1 + x) / (1 - x)) + * + * atanh(|x| > 1) = NaN + * atanh(NaN) = NaN + * atanh(Infinity) = NaN + * atanh(-Infinity) = NaN + * atanh(0) = 0 + * atanh(-0) = -0 + * atanh(1) = Infinity + * atanh(-1) = -Infinity + * + */ +P.inverseHyperbolicTangent = P.atanh = function () { + var pr, rm, wpr, xsd, + x = this, + Ctor = x.constructor; + + if (!x.isFinite()) return new Ctor(NaN); + if (x.e >= 0) return new Ctor(x.abs().eq(1) ? x.s / 0 : x.isZero() ? x : NaN); + + pr = Ctor.precision; + rm = Ctor.rounding; + xsd = x.sd(); + + if (Math.max(xsd, pr) < 2 * -x.e - 1) return finalise(new Ctor(x), pr, rm, true); + + Ctor.precision = wpr = xsd - x.e; + + x = divide(x.plus(1), new Ctor(1).minus(x), wpr + pr, 1); + + Ctor.precision = pr + 4; + Ctor.rounding = 1; + + x = x.ln(); + + Ctor.precision = pr; + Ctor.rounding = rm; + + return x.times(0.5); +}; + + +/* + * Return a new Decimal whose value is the arcsine (inverse sine) in radians of the value of this + * Decimal. + * + * Domain: [-Infinity, Infinity] + * Range: [-pi/2, pi/2] + * + * asin(x) = 2*atan(x/(1 + sqrt(1 - x^2))) + * + * asin(0) = 0 + * asin(-0) = -0 + * asin(1/2) = pi/6 + * asin(-1/2) = -pi/6 + * asin(1) = pi/2 + * asin(-1) = -pi/2 + * asin(|x| > 1) = NaN + * asin(NaN) = NaN + * + * TODO? Compare performance of Taylor series. + * + */ +P.inverseSine = P.asin = function () { + var halfPi, k, + pr, rm, + x = this, + Ctor = x.constructor; + + if (x.isZero()) return new Ctor(x); + + k = x.abs().cmp(1); + pr = Ctor.precision; + rm = Ctor.rounding; + + if (k !== -1) { + + // |x| is 1 + if (k === 0) { + halfPi = getPi(Ctor, pr + 4, rm).times(0.5); + halfPi.s = x.s; + return halfPi; + } + + // |x| > 1 or x is NaN + return new Ctor(NaN); + } + + // TODO? Special case asin(1/2) = pi/6 and asin(-1/2) = -pi/6 + + Ctor.precision = pr + 6; + Ctor.rounding = 1; + + x = x.div(new Ctor(1).minus(x.times(x)).sqrt().plus(1)).atan(); + + Ctor.precision = pr; + Ctor.rounding = rm; + + return x.times(2); +}; + + +/* + * Return a new Decimal whose value is the arctangent (inverse tangent) in radians of the value + * of this Decimal. + * + * Domain: [-Infinity, Infinity] + * Range: [-pi/2, pi/2] + * + * atan(x) = x - x^3/3 + x^5/5 - x^7/7 + ... + * + * atan(0) = 0 + * atan(-0) = -0 + * atan(1) = pi/4 + * atan(-1) = -pi/4 + * atan(Infinity) = pi/2 + * atan(-Infinity) = -pi/2 + * atan(NaN) = NaN + * + */ +P.inverseTangent = P.atan = function () { + var i, j, k, n, px, t, r, wpr, x2, + x = this, + Ctor = x.constructor, + pr = Ctor.precision, + rm = Ctor.rounding; + + if (!x.isFinite()) { + if (!x.s) return new Ctor(NaN); + if (pr + 4 <= PI_PRECISION) { + r = getPi(Ctor, pr + 4, rm).times(0.5); + r.s = x.s; + return r; + } + } else if (x.isZero()) { + return new Ctor(x); + } else if (x.abs().eq(1) && pr + 4 <= PI_PRECISION) { + r = getPi(Ctor, pr + 4, rm).times(0.25); + r.s = x.s; + return r; + } + + Ctor.precision = wpr = pr + 10; + Ctor.rounding = 1; + + // TODO? if (x >= 1 && pr <= PI_PRECISION) atan(x) = halfPi * x.s - atan(1 / x); + + // Argument reduction + // Ensure |x| < 0.42 + // atan(x) = 2 * atan(x / (1 + sqrt(1 + x^2))) + + k = Math.min(28, wpr / LOG_BASE + 2 | 0); + + for (i = k; i; --i) x = x.div(x.times(x).plus(1).sqrt().plus(1)); + + external = false; + + j = Math.ceil(wpr / LOG_BASE); + n = 1; + x2 = x.times(x); + r = new Ctor(x); + px = x; + + // atan(x) = x - x^3/3 + x^5/5 - x^7/7 + ... + for (; i !== -1;) { + px = px.times(x2); + t = r.minus(px.div(n += 2)); + + px = px.times(x2); + r = t.plus(px.div(n += 2)); + + if (r.d[j] !== void 0) for (i = j; r.d[i] === t.d[i] && i--;); + } + + if (k) r = r.times(2 << (k - 1)); + + external = true; + + return finalise(r, Ctor.precision = pr, Ctor.rounding = rm, true); +}; + + +/* + * Return true if the value of this Decimal is a finite number, otherwise return false. + * + */ +P.isFinite = function () { + return !!this.d; +}; + + +/* + * Return true if the value of this Decimal is an integer, otherwise return false. + * + */ +P.isInteger = P.isInt = function () { + return !!this.d && mathfloor(this.e / LOG_BASE) > this.d.length - 2; +}; + + +/* + * Return true if the value of this Decimal is NaN, otherwise return false. + * + */ +P.isNaN = function () { + return !this.s; +}; + + +/* + * Return true if the value of this Decimal is negative, otherwise return false. + * + */ +P.isNegative = P.isNeg = function () { + return this.s < 0; +}; + + +/* + * Return true if the value of this Decimal is positive, otherwise return false. + * + */ +P.isPositive = P.isPos = function () { + return this.s > 0; +}; + + +/* + * Return true if the value of this Decimal is 0 or -0, otherwise return false. + * + */ +P.isZero = function () { + return !!this.d && this.d[0] === 0; +}; + + +/* + * Return true if the value of this Decimal is less than `y`, otherwise return false. + * + */ +P.lessThan = P.lt = function (y) { + return this.cmp(y) < 0; +}; + + +/* + * Return true if the value of this Decimal is less than or equal to `y`, otherwise return false. + * + */ +P.lessThanOrEqualTo = P.lte = function (y) { + return this.cmp(y) < 1; +}; + + +/* + * Return the logarithm of the value of this Decimal to the specified base, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * If no base is specified, return log[10](arg). + * + * log[base](arg) = ln(arg) / ln(base) + * + * The result will always be correctly rounded if the base of the log is 10, and 'almost always' + * otherwise: + * + * Depending on the rounding mode, the result may be incorrectly rounded if the first fifteen + * rounding digits are [49]99999999999999 or [50]00000000000000. In that case, the maximum error + * between the result and the correctly rounded result will be one ulp (unit in the last place). + * + * log[-b](a) = NaN + * log[0](a) = NaN + * log[1](a) = NaN + * log[NaN](a) = NaN + * log[Infinity](a) = NaN + * log[b](0) = -Infinity + * log[b](-0) = -Infinity + * log[b](-a) = NaN + * log[b](1) = 0 + * log[b](Infinity) = Infinity + * log[b](NaN) = NaN + * + * [base] {number|string|bigint|Decimal} The base of the logarithm. + * + */ +P.logarithm = P.log = function (base) { + var isBase10, d, denominator, k, inf, num, sd, r, + arg = this, + Ctor = arg.constructor, + pr = Ctor.precision, + rm = Ctor.rounding, + guard = 5; + + // Default base is 10. + if (base == null) { + base = new Ctor(10); + isBase10 = true; + } else { + base = new Ctor(base); + d = base.d; + + // Return NaN if base is negative, or non-finite, or is 0 or 1. + if (base.s < 0 || !d || !d[0] || base.eq(1)) return new Ctor(NaN); + + isBase10 = base.eq(10); + } + + d = arg.d; + + // Is arg negative, non-finite, 0 or 1? + if (arg.s < 0 || !d || !d[0] || arg.eq(1)) { + return new Ctor(d && !d[0] ? -1 / 0 : arg.s != 1 ? NaN : d ? 0 : 1 / 0); + } + + // The result will have a non-terminating decimal expansion if base is 10 and arg is not an + // integer power of 10. + if (isBase10) { + if (d.length > 1) { + inf = true; + } else { + for (k = d[0]; k % 10 === 0;) k /= 10; + inf = k !== 1; + } + } + + external = false; + sd = pr + guard; + num = naturalLogarithm(arg, sd); + denominator = isBase10 ? getLn10(Ctor, sd + 10) : naturalLogarithm(base, sd); + + // The result will have 5 rounding digits. + r = divide(num, denominator, sd, 1); + + // If at a rounding boundary, i.e. the result's rounding digits are [49]9999 or [50]0000, + // calculate 10 further digits. + // + // If the result is known to have an infinite decimal expansion, repeat this until it is clear + // that the result is above or below the boundary. Otherwise, if after calculating the 10 + // further digits, the last 14 are nines, round up and assume the result is exact. + // Also assume the result is exact if the last 14 are zero. + // + // Example of a result that will be incorrectly rounded: + // log[1048576](4503599627370502) = 2.60000000000000009610279511444746... + // The above result correctly rounded using ROUND_CEIL to 1 decimal place should be 2.7, but it + // will be given as 2.6 as there are 15 zeros immediately after the requested decimal place, so + // the exact result would be assumed to be 2.6, which rounded using ROUND_CEIL to 1 decimal + // place is still 2.6. + if (checkRoundingDigits(r.d, k = pr, rm)) { + + do { + sd += 10; + num = naturalLogarithm(arg, sd); + denominator = isBase10 ? getLn10(Ctor, sd + 10) : naturalLogarithm(base, sd); + r = divide(num, denominator, sd, 1); + + if (!inf) { + + // Check for 14 nines from the 2nd rounding digit, as the first may be 4. + if (+digitsToString(r.d).slice(k + 1, k + 15) + 1 == 1e14) { + r = finalise(r, pr + 1, 0); + } + + break; + } + } while (checkRoundingDigits(r.d, k += 10, rm)); + } + + external = true; + + return finalise(r, pr, rm); +}; + + +/* + * Return a new Decimal whose value is the maximum of the arguments and the value of this Decimal. + * + * arguments {number|string|bigint|Decimal} + * +P.max = function () { + Array.prototype.push.call(arguments, this); + return maxOrMin(this.constructor, arguments, -1); +}; + */ + + +/* + * Return a new Decimal whose value is the minimum of the arguments and the value of this Decimal. + * + * arguments {number|string|bigint|Decimal} + * +P.min = function () { + Array.prototype.push.call(arguments, this); + return maxOrMin(this.constructor, arguments, 1); +}; + */ + + +/* + * n - 0 = n + * n - N = N + * n - I = -I + * 0 - n = -n + * 0 - 0 = 0 + * 0 - N = N + * 0 - I = -I + * N - n = N + * N - 0 = N + * N - N = N + * N - I = N + * I - n = I + * I - 0 = I + * I - N = N + * I - I = N + * + * Return a new Decimal whose value is the value of this Decimal minus `y`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + */ +P.minus = P.sub = function (y) { + var d, e, i, j, k, len, pr, rm, xd, xe, xLTy, yd, + x = this, + Ctor = x.constructor; + + y = new Ctor(y); + + // If either is not finite... + if (!x.d || !y.d) { + + // Return NaN if either is NaN. + if (!x.s || !y.s) y = new Ctor(NaN); + + // Return y negated if x is finite and y is ±Infinity. + else if (x.d) y.s = -y.s; + + // Return x if y is finite and x is ±Infinity. + // Return x if both are ±Infinity with different signs. + // Return NaN if both are ±Infinity with the same sign. + else y = new Ctor(y.d || x.s !== y.s ? x : NaN); + + return y; + } + + // If signs differ... + if (x.s != y.s) { + y.s = -y.s; + return x.plus(y); + } + + xd = x.d; + yd = y.d; + pr = Ctor.precision; + rm = Ctor.rounding; + + // If either is zero... + if (!xd[0] || !yd[0]) { + + // Return y negated if x is zero and y is non-zero. + if (yd[0]) y.s = -y.s; + + // Return x if y is zero and x is non-zero. + else if (xd[0]) y = new Ctor(x); + + // Return zero if both are zero. + // From IEEE 754 (2008) 6.3: 0 - 0 = -0 - -0 = -0 when rounding to -Infinity. + else return new Ctor(rm === 3 ? -0 : 0); + + return external ? finalise(y, pr, rm) : y; + } + + // x and y are finite, non-zero numbers with the same sign. + + // Calculate base 1e7 exponents. + e = mathfloor(y.e / LOG_BASE); + xe = mathfloor(x.e / LOG_BASE); + + xd = xd.slice(); + k = xe - e; + + // If base 1e7 exponents differ... + if (k) { + xLTy = k < 0; + + if (xLTy) { + d = xd; + k = -k; + len = yd.length; + } else { + d = yd; + e = xe; + len = xd.length; + } + + // Numbers with massively different exponents would result in a very high number of + // zeros needing to be prepended, but this can be avoided while still ensuring correct + // rounding by limiting the number of zeros to `Math.ceil(pr / LOG_BASE) + 2`. + i = Math.max(Math.ceil(pr / LOG_BASE), len) + 2; + + if (k > i) { + k = i; + d.length = 1; + } + + // Prepend zeros to equalise exponents. + d.reverse(); + for (i = k; i--;) d.push(0); + d.reverse(); + + // Base 1e7 exponents equal. + } else { + + // Check digits to determine which is the bigger number. + + i = xd.length; + len = yd.length; + xLTy = i < len; + if (xLTy) len = i; + + for (i = 0; i < len; i++) { + if (xd[i] != yd[i]) { + xLTy = xd[i] < yd[i]; + break; + } + } + + k = 0; + } + + if (xLTy) { + d = xd; + xd = yd; + yd = d; + y.s = -y.s; + } + + len = xd.length; + + // Append zeros to `xd` if shorter. + // Don't add zeros to `yd` if shorter as subtraction only needs to start at `yd` length. + for (i = yd.length - len; i > 0; --i) xd[len++] = 0; + + // Subtract yd from xd. + for (i = yd.length; i > k;) { + + if (xd[--i] < yd[i]) { + for (j = i; j && xd[--j] === 0;) xd[j] = BASE - 1; + --xd[j]; + xd[i] += BASE; + } + + xd[i] -= yd[i]; + } + + // Remove trailing zeros. + for (; xd[--len] === 0;) xd.pop(); + + // Remove leading zeros and adjust exponent accordingly. + for (; xd[0] === 0; xd.shift()) --e; + + // Zero? + if (!xd[0]) return new Ctor(rm === 3 ? -0 : 0); + + y.d = xd; + y.e = getBase10Exponent(xd, e); + + return external ? finalise(y, pr, rm) : y; +}; + + +/* + * n % 0 = N + * n % N = N + * n % I = n + * 0 % n = 0 + * -0 % n = -0 + * 0 % 0 = N + * 0 % N = N + * 0 % I = 0 + * N % n = N + * N % 0 = N + * N % N = N + * N % I = N + * I % n = N + * I % 0 = N + * I % N = N + * I % I = N + * + * Return a new Decimal whose value is the value of this Decimal modulo `y`, rounded to + * `precision` significant digits using rounding mode `rounding`. + * + * The result depends on the modulo mode. + * + */ +P.modulo = P.mod = function (y) { + var q, + x = this, + Ctor = x.constructor; + + y = new Ctor(y); + + // Return NaN if x is ±Infinity or NaN, or y is NaN or ±0. + if (!x.d || !y.s || y.d && !y.d[0]) return new Ctor(NaN); + + // Return x if y is ±Infinity or x is ±0. + if (!y.d || x.d && !x.d[0]) { + return finalise(new Ctor(x), Ctor.precision, Ctor.rounding); + } + + // Prevent rounding of intermediate calculations. + external = false; + + if (Ctor.modulo == 9) { + + // Euclidian division: q = sign(y) * floor(x / abs(y)) + // result = x - q * y where 0 <= result < abs(y) + q = divide(x, y.abs(), 0, 3, 1); + q.s *= y.s; + } else { + q = divide(x, y, 0, Ctor.modulo, 1); + } + + q = q.times(y); + + external = true; + + return x.minus(q); +}; + + +/* + * Return a new Decimal whose value is the natural exponential of the value of this Decimal, + * i.e. the base e raised to the power the value of this Decimal, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + */ +P.naturalExponential = P.exp = function () { + return naturalExponential(this); +}; + + +/* + * Return a new Decimal whose value is the natural logarithm of the value of this Decimal, + * rounded to `precision` significant digits using rounding mode `rounding`. + * + */ +P.naturalLogarithm = P.ln = function () { + return naturalLogarithm(this); +}; + + +/* + * Return a new Decimal whose value is the value of this Decimal negated, i.e. as if multiplied by + * -1. + * + */ +P.negated = P.neg = function () { + var x = new this.constructor(this); + x.s = -x.s; + return finalise(x); +}; + + +/* + * n + 0 = n + * n + N = N + * n + I = I + * 0 + n = n + * 0 + 0 = 0 + * 0 + N = N + * 0 + I = I + * N + n = N + * N + 0 = N + * N + N = N + * N + I = N + * I + n = I + * I + 0 = I + * I + N = N + * I + I = I + * + * Return a new Decimal whose value is the value of this Decimal plus `y`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + */ +P.plus = P.add = function (y) { + var carry, d, e, i, k, len, pr, rm, xd, yd, + x = this, + Ctor = x.constructor; + + y = new Ctor(y); + + // If either is not finite... + if (!x.d || !y.d) { + + // Return NaN if either is NaN. + if (!x.s || !y.s) y = new Ctor(NaN); + + // Return x if y is finite and x is ±Infinity. + // Return x if both are ±Infinity with the same sign. + // Return NaN if both are ±Infinity with different signs. + // Return y if x is finite and y is ±Infinity. + else if (!x.d) y = new Ctor(y.d || x.s === y.s ? x : NaN); + + return y; + } + + // If signs differ... + if (x.s != y.s) { + y.s = -y.s; + return x.minus(y); + } + + xd = x.d; + yd = y.d; + pr = Ctor.precision; + rm = Ctor.rounding; + + // If either is zero... + if (!xd[0] || !yd[0]) { + + // Return x if y is zero. + // Return y if y is non-zero. + if (!yd[0]) y = new Ctor(x); + + return external ? finalise(y, pr, rm) : y; + } + + // x and y are finite, non-zero numbers with the same sign. + + // Calculate base 1e7 exponents. + k = mathfloor(x.e / LOG_BASE); + e = mathfloor(y.e / LOG_BASE); + + xd = xd.slice(); + i = k - e; + + // If base 1e7 exponents differ... + if (i) { + + if (i < 0) { + d = xd; + i = -i; + len = yd.length; + } else { + d = yd; + e = k; + len = xd.length; + } + + // Limit number of zeros prepended to max(ceil(pr / LOG_BASE), len) + 1. + k = Math.ceil(pr / LOG_BASE); + len = k > len ? k + 1 : len + 1; + + if (i > len) { + i = len; + d.length = 1; + } + + // Prepend zeros to equalise exponents. Note: Faster to use reverse then do unshifts. + d.reverse(); + for (; i--;) d.push(0); + d.reverse(); + } + + len = xd.length; + i = yd.length; + + // If yd is longer than xd, swap xd and yd so xd points to the longer array. + if (len - i < 0) { + i = len; + d = yd; + yd = xd; + xd = d; + } + + // Only start adding at yd.length - 1 as the further digits of xd can be left as they are. + for (carry = 0; i;) { + carry = (xd[--i] = xd[i] + yd[i] + carry) / BASE | 0; + xd[i] %= BASE; + } + + if (carry) { + xd.unshift(carry); + ++e; + } + + // Remove trailing zeros. + // No need to check for zero, as +x + +y != 0 && -x + -y != 0 + for (len = xd.length; xd[--len] == 0;) xd.pop(); + + y.d = xd; + y.e = getBase10Exponent(xd, e); + + return external ? finalise(y, pr, rm) : y; +}; + + +/* + * Return the number of significant digits of the value of this Decimal. + * + * [z] {boolean|number} Whether to count integer-part trailing zeros: true, false, 1 or 0. + * + */ +P.precision = P.sd = function (z) { + var k, + x = this; + + if (z !== void 0 && z !== !!z && z !== 1 && z !== 0) throw Error(invalidArgument + z); + + if (x.d) { + k = getPrecision(x.d); + if (z && x.e + 1 > k) k = x.e + 1; + } else { + k = NaN; + } + + return k; +}; + + +/* + * Return a new Decimal whose value is the value of this Decimal rounded to a whole number using + * rounding mode `rounding`. + * + */ +P.round = function () { + var x = this, + Ctor = x.constructor; + + return finalise(new Ctor(x), x.e + 1, Ctor.rounding); +}; + + +/* + * Return a new Decimal whose value is the sine of the value in radians of this Decimal. + * + * Domain: [-Infinity, Infinity] + * Range: [-1, 1] + * + * sin(x) = x - x^3/3! + x^5/5! - ... + * + * sin(0) = 0 + * sin(-0) = -0 + * sin(Infinity) = NaN + * sin(-Infinity) = NaN + * sin(NaN) = NaN + * + */ +P.sine = P.sin = function () { + var pr, rm, + x = this, + Ctor = x.constructor; + + if (!x.isFinite()) return new Ctor(NaN); + if (x.isZero()) return new Ctor(x); + + pr = Ctor.precision; + rm = Ctor.rounding; + Ctor.precision = pr + Math.max(x.e, x.sd()) + LOG_BASE; + Ctor.rounding = 1; + + x = sine(Ctor, toLessThanHalfPi(Ctor, x)); + + Ctor.precision = pr; + Ctor.rounding = rm; + + return finalise(quadrant > 2 ? x.neg() : x, pr, rm, true); +}; + + +/* + * Return a new Decimal whose value is the square root of this Decimal, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * sqrt(-n) = N + * sqrt(N) = N + * sqrt(-I) = N + * sqrt(I) = I + * sqrt(0) = 0 + * sqrt(-0) = -0 + * + */ +P.squareRoot = P.sqrt = function () { + var m, n, sd, r, rep, t, + x = this, + d = x.d, + e = x.e, + s = x.s, + Ctor = x.constructor; + + // Negative/NaN/Infinity/zero? + if (s !== 1 || !d || !d[0]) { + return new Ctor(!s || s < 0 && (!d || d[0]) ? NaN : d ? x : 1 / 0); + } + + external = false; + + // Initial estimate. + s = Math.sqrt(+x); + + // Math.sqrt underflow/overflow? + // Pass x to Math.sqrt as integer, then adjust the exponent of the result. + if (s == 0 || s == 1 / 0) { + n = digitsToString(d); + + if ((n.length + e) % 2 == 0) n += '0'; + s = Math.sqrt(n); + e = mathfloor((e + 1) / 2) - (e < 0 || e % 2); + + if (s == 1 / 0) { + n = '5e' + e; + } else { + n = s.toExponential(); + n = n.slice(0, n.indexOf('e') + 1) + e; + } + + r = new Ctor(n); + } else { + r = new Ctor(s.toString()); + } + + sd = (e = Ctor.precision) + 3; + + // Newton-Raphson iteration. + for (;;) { + t = r; + r = t.plus(divide(x, t, sd + 2, 1)).times(0.5); + + // TODO? Replace with for-loop and checkRoundingDigits. + if (digitsToString(t.d).slice(0, sd) === (n = digitsToString(r.d)).slice(0, sd)) { + n = n.slice(sd - 3, sd + 1); + + // The 4th rounding digit may be in error by -1 so if the 4 rounding digits are 9999 or + // 4999, i.e. approaching a rounding boundary, continue the iteration. + if (n == '9999' || !rep && n == '4999') { + + // On the first iteration only, check to see if rounding up gives the exact result as the + // nines may infinitely repeat. + if (!rep) { + finalise(t, e + 1, 0); + + if (t.times(t).eq(x)) { + r = t; + break; + } + } + + sd += 4; + rep = 1; + } else { + + // If the rounding digits are null, 0{0,4} or 50{0,3}, check for an exact result. + // If not, then there are further digits and m will be truthy. + if (!+n || !+n.slice(1) && n.charAt(0) == '5') { + + // Truncate to the first rounding digit. + finalise(r, e + 1, 1); + m = !r.times(r).eq(x); + } + + break; + } + } + } + + external = true; + + return finalise(r, e, Ctor.rounding, m); +}; + + +/* + * Return a new Decimal whose value is the tangent of the value in radians of this Decimal. + * + * Domain: [-Infinity, Infinity] + * Range: [-Infinity, Infinity] + * + * tan(0) = 0 + * tan(-0) = -0 + * tan(Infinity) = NaN + * tan(-Infinity) = NaN + * tan(NaN) = NaN + * + */ +P.tangent = P.tan = function () { + var pr, rm, + x = this, + Ctor = x.constructor; + + if (!x.isFinite()) return new Ctor(NaN); + if (x.isZero()) return new Ctor(x); + + pr = Ctor.precision; + rm = Ctor.rounding; + Ctor.precision = pr + 10; + Ctor.rounding = 1; + + x = x.sin(); + x.s = 1; + x = divide(x, new Ctor(1).minus(x.times(x)).sqrt(), pr + 10, 0); + + Ctor.precision = pr; + Ctor.rounding = rm; + + return finalise(quadrant == 2 || quadrant == 4 ? x.neg() : x, pr, rm, true); +}; + + +/* + * n * 0 = 0 + * n * N = N + * n * I = I + * 0 * n = 0 + * 0 * 0 = 0 + * 0 * N = N + * 0 * I = N + * N * n = N + * N * 0 = N + * N * N = N + * N * I = N + * I * n = I + * I * 0 = N + * I * N = N + * I * I = I + * + * Return a new Decimal whose value is this Decimal times `y`, rounded to `precision` significant + * digits using rounding mode `rounding`. + * + */ +P.times = P.mul = function (y) { + var carry, e, i, k, r, rL, t, xdL, ydL, + x = this, + Ctor = x.constructor, + xd = x.d, + yd = (y = new Ctor(y)).d; + + y.s *= x.s; + + // If either is NaN, ±Infinity or ±0... + if (!xd || !xd[0] || !yd || !yd[0]) { + + return new Ctor(!y.s || xd && !xd[0] && !yd || yd && !yd[0] && !xd + + // Return NaN if either is NaN. + // Return NaN if x is ±0 and y is ±Infinity, or y is ±0 and x is ±Infinity. + ? NaN + + // Return ±Infinity if either is ±Infinity. + // Return ±0 if either is ±0. + : !xd || !yd ? y.s / 0 : y.s * 0); + } + + e = mathfloor(x.e / LOG_BASE) + mathfloor(y.e / LOG_BASE); + xdL = xd.length; + ydL = yd.length; + + // Ensure xd points to the longer array. + if (xdL < ydL) { + r = xd; + xd = yd; + yd = r; + rL = xdL; + xdL = ydL; + ydL = rL; + } + + // Initialise the result array with zeros. + r = []; + rL = xdL + ydL; + for (i = rL; i--;) r.push(0); + + // Multiply! + for (i = ydL; --i >= 0;) { + carry = 0; + for (k = xdL + i; k > i;) { + t = r[k] + yd[i] * xd[k - i - 1] + carry; + r[k--] = t % BASE | 0; + carry = t / BASE | 0; + } + + r[k] = (r[k] + carry) % BASE | 0; + } + + // Remove trailing zeros. + for (; !r[--rL];) r.pop(); + + if (carry) ++e; + else r.shift(); + + y.d = r; + y.e = getBase10Exponent(r, e); + + return external ? finalise(y, Ctor.precision, Ctor.rounding) : y; +}; + + +/* + * Return a string representing the value of this Decimal in base 2, round to `sd` significant + * digits using rounding mode `rm`. + * + * If the optional `sd` argument is present then return binary exponential notation. + * + * [sd] {number} Significant digits. Integer, 1 to MAX_DIGITS inclusive. + * [rm] {number} Rounding mode. Integer, 0 to 8 inclusive. + * + */ +P.toBinary = function (sd, rm) { + return toStringBinary(this, 2, sd, rm); +}; + + +/* + * Return a new Decimal whose value is the value of this Decimal rounded to a maximum of `dp` + * decimal places using rounding mode `rm` or `rounding` if `rm` is omitted. + * + * If `dp` is omitted, return a new Decimal whose value is the value of this Decimal. + * + * [dp] {number} Decimal places. Integer, 0 to MAX_DIGITS inclusive. + * [rm] {number} Rounding mode. Integer, 0 to 8 inclusive. + * + */ +P.toDecimalPlaces = P.toDP = function (dp, rm) { + var x = this, + Ctor = x.constructor; + + x = new Ctor(x); + if (dp === void 0) return x; + + checkInt32(dp, 0, MAX_DIGITS); + + if (rm === void 0) rm = Ctor.rounding; + else checkInt32(rm, 0, 8); + + return finalise(x, dp + x.e + 1, rm); +}; + + +/* + * Return a string representing the value of this Decimal in exponential notation rounded to + * `dp` fixed decimal places using rounding mode `rounding`. + * + * [dp] {number} Decimal places. Integer, 0 to MAX_DIGITS inclusive. + * [rm] {number} Rounding mode. Integer, 0 to 8 inclusive. + * + */ +P.toExponential = function (dp, rm) { + var str, + x = this, + Ctor = x.constructor; + + if (dp === void 0) { + str = finiteToString(x, true); + } else { + checkInt32(dp, 0, MAX_DIGITS); + + if (rm === void 0) rm = Ctor.rounding; + else checkInt32(rm, 0, 8); + + x = finalise(new Ctor(x), dp + 1, rm); + str = finiteToString(x, true, dp + 1); + } + + return x.isNeg() && !x.isZero() ? '-' + str : str; +}; + + +/* + * Return a string representing the value of this Decimal in normal (fixed-point) notation to + * `dp` fixed decimal places and rounded using rounding mode `rm` or `rounding` if `rm` is + * omitted. + * + * As with JavaScript numbers, (-0).toFixed(0) is '0', but e.g. (-0.00001).toFixed(0) is '-0'. + * + * [dp] {number} Decimal places. Integer, 0 to MAX_DIGITS inclusive. + * [rm] {number} Rounding mode. Integer, 0 to 8 inclusive. + * + * (-0).toFixed(0) is '0', but (-0.1).toFixed(0) is '-0'. + * (-0).toFixed(1) is '0.0', but (-0.01).toFixed(1) is '-0.0'. + * (-0).toFixed(3) is '0.000'. + * (-0.5).toFixed(0) is '-0'. + * + */ +P.toFixed = function (dp, rm) { + var str, y, + x = this, + Ctor = x.constructor; + + if (dp === void 0) { + str = finiteToString(x); + } else { + checkInt32(dp, 0, MAX_DIGITS); + + if (rm === void 0) rm = Ctor.rounding; + else checkInt32(rm, 0, 8); + + y = finalise(new Ctor(x), dp + x.e + 1, rm); + str = finiteToString(y, false, dp + y.e + 1); + } + + // To determine whether to add the minus sign look at the value before it was rounded, + // i.e. look at `x` rather than `y`. + return x.isNeg() && !x.isZero() ? '-' + str : str; +}; + + +/* + * Return an array representing the value of this Decimal as a simple fraction with an integer + * numerator and an integer denominator. + * + * The denominator will be a positive non-zero value less than or equal to the specified maximum + * denominator. If a maximum denominator is not specified, the denominator will be the lowest + * value necessary to represent the number exactly. + * + * [maxD] {number|string|bigint|Decimal} Maximum denominator. Integer >= 1 and < Infinity. + * + */ +P.toFraction = function (maxD) { + var d, d0, d1, d2, e, k, n, n0, n1, pr, q, r, + x = this, + xd = x.d, + Ctor = x.constructor; + + if (!xd) return new Ctor(x); + + n1 = d0 = new Ctor(1); + d1 = n0 = new Ctor(0); + + d = new Ctor(d1); + e = d.e = getPrecision(xd) - x.e - 1; + k = e % LOG_BASE; + d.d[0] = mathpow(10, k < 0 ? LOG_BASE + k : k); + + if (maxD == null) { + + // d is 10**e, the minimum max-denominator needed. + maxD = e > 0 ? d : n1; + } else { + n = new Ctor(maxD); + if (!n.isInt() || n.lt(n1)) throw Error(invalidArgument + n); + maxD = n.gt(d) ? (e > 0 ? d : n1) : n; + } + + external = false; + n = new Ctor(digitsToString(xd)); + pr = Ctor.precision; + Ctor.precision = e = xd.length * LOG_BASE * 2; + + for (;;) { + q = divide(n, d, 0, 1, 1); + d2 = d0.plus(q.times(d1)); + if (d2.cmp(maxD) == 1) break; + d0 = d1; + d1 = d2; + d2 = n1; + n1 = n0.plus(q.times(d2)); + n0 = d2; + d2 = d; + d = n.minus(q.times(d2)); + n = d2; + } + + d2 = divide(maxD.minus(d0), d1, 0, 1, 1); + n0 = n0.plus(d2.times(n1)); + d0 = d0.plus(d2.times(d1)); + n0.s = n1.s = x.s; + + // Determine which fraction is closer to x, n0/d0 or n1/d1? + r = divide(n1, d1, e, 1).minus(x).abs().cmp(divide(n0, d0, e, 1).minus(x).abs()) < 1 + ? [n1, d1] : [n0, d0]; + + Ctor.precision = pr; + external = true; + + return r; +}; + + +/* + * Return a string representing the value of this Decimal in base 16, round to `sd` significant + * digits using rounding mode `rm`. + * + * If the optional `sd` argument is present then return binary exponential notation. + * + * [sd] {number} Significant digits. Integer, 1 to MAX_DIGITS inclusive. + * [rm] {number} Rounding mode. Integer, 0 to 8 inclusive. + * + */ +P.toHexadecimal = P.toHex = function (sd, rm) { + return toStringBinary(this, 16, sd, rm); +}; + + +/* + * Returns a new Decimal whose value is the nearest multiple of `y` in the direction of rounding + * mode `rm`, or `Decimal.rounding` if `rm` is omitted, to the value of this Decimal. + * + * The return value will always have the same sign as this Decimal, unless either this Decimal + * or `y` is NaN, in which case the return value will be also be NaN. + * + * The return value is not affected by the value of `precision`. + * + * y {number|string|bigint|Decimal} The magnitude to round to a multiple of. + * [rm] {number} Rounding mode. Integer, 0 to 8 inclusive. + * + * 'toNearest() rounding mode not an integer: {rm}' + * 'toNearest() rounding mode out of range: {rm}' + * + */ +P.toNearest = function (y, rm) { + var x = this, + Ctor = x.constructor; + + x = new Ctor(x); + + if (y == null) { + + // If x is not finite, return x. + if (!x.d) return x; + + y = new Ctor(1); + rm = Ctor.rounding; + } else { + y = new Ctor(y); + if (rm === void 0) { + rm = Ctor.rounding; + } else { + checkInt32(rm, 0, 8); + } + + // If x is not finite, return x if y is not NaN, else NaN. + if (!x.d) return y.s ? x : y; + + // If y is not finite, return Infinity with the sign of x if y is Infinity, else NaN. + if (!y.d) { + if (y.s) y.s = x.s; + return y; + } + } + + // If y is not zero, calculate the nearest multiple of y to x. + if (y.d[0]) { + external = false; + x = divide(x, y, 0, rm, 1).times(y); + external = true; + finalise(x); + + // If y is zero, return zero with the sign of x. + } else { + y.s = x.s; + x = y; + } + + return x; +}; + + +/* + * Return the value of this Decimal converted to a number primitive. + * Zero keeps its sign. + * + */ +P.toNumber = function () { + return +this; +}; + + +/* + * Return a string representing the value of this Decimal in base 8, round to `sd` significant + * digits using rounding mode `rm`. + * + * If the optional `sd` argument is present then return binary exponential notation. + * + * [sd] {number} Significant digits. Integer, 1 to MAX_DIGITS inclusive. + * [rm] {number} Rounding mode. Integer, 0 to 8 inclusive. + * + */ +P.toOctal = function (sd, rm) { + return toStringBinary(this, 8, sd, rm); +}; + + +/* + * Return a new Decimal whose value is the value of this Decimal raised to the power `y`, rounded + * to `precision` significant digits using rounding mode `rounding`. + * + * ECMAScript compliant. + * + * pow(x, NaN) = NaN + * pow(x, ±0) = 1 + + * pow(NaN, non-zero) = NaN + * pow(abs(x) > 1, +Infinity) = +Infinity + * pow(abs(x) > 1, -Infinity) = +0 + * pow(abs(x) == 1, ±Infinity) = NaN + * pow(abs(x) < 1, +Infinity) = +0 + * pow(abs(x) < 1, -Infinity) = +Infinity + * pow(+Infinity, y > 0) = +Infinity + * pow(+Infinity, y < 0) = +0 + * pow(-Infinity, odd integer > 0) = -Infinity + * pow(-Infinity, even integer > 0) = +Infinity + * pow(-Infinity, odd integer < 0) = -0 + * pow(-Infinity, even integer < 0) = +0 + * pow(+0, y > 0) = +0 + * pow(+0, y < 0) = +Infinity + * pow(-0, odd integer > 0) = -0 + * pow(-0, even integer > 0) = +0 + * pow(-0, odd integer < 0) = -Infinity + * pow(-0, even integer < 0) = +Infinity + * pow(finite x < 0, finite non-integer) = NaN + * + * For non-integer or very large exponents pow(x, y) is calculated using + * + * x^y = exp(y*ln(x)) + * + * Assuming the first 15 rounding digits are each equally likely to be any digit 0-9, the + * probability of an incorrectly rounded result + * P([49]9{14} | [50]0{14}) = 2 * 0.2 * 10^-14 = 4e-15 = 1/2.5e+14 + * i.e. 1 in 250,000,000,000,000 + * + * If a result is incorrectly rounded the maximum error will be 1 ulp (unit in last place). + * + * y {number|string|bigint|Decimal} The power to which to raise this Decimal. + * + */ +P.toPower = P.pow = function (y) { + var e, k, pr, r, rm, s, + x = this, + Ctor = x.constructor, + yn = +(y = new Ctor(y)); + + // Either ±Infinity, NaN or ±0? + if (!x.d || !y.d || !x.d[0] || !y.d[0]) return new Ctor(mathpow(+x, yn)); + + x = new Ctor(x); + + if (x.eq(1)) return x; + + pr = Ctor.precision; + rm = Ctor.rounding; + + if (y.eq(1)) return finalise(x, pr, rm); + + // y exponent + e = mathfloor(y.e / LOG_BASE); + + // If y is a small integer use the 'exponentiation by squaring' algorithm. + if (e >= y.d.length - 1 && (k = yn < 0 ? -yn : yn) <= MAX_SAFE_INTEGER) { + r = intPow(Ctor, x, k, pr); + return y.s < 0 ? new Ctor(1).div(r) : finalise(r, pr, rm); + } + + s = x.s; + + // if x is negative + if (s < 0) { + + // if y is not an integer + if (e < y.d.length - 1) return new Ctor(NaN); + + // Result is positive if x is negative and the last digit of integer y is even. + if ((y.d[e] & 1) == 0) s = 1; + + // if x.eq(-1) + if (x.e == 0 && x.d[0] == 1 && x.d.length == 1) { + x.s = s; + return x; + } + } + + // Estimate result exponent. + // x^y = 10^e, where e = y * log10(x) + // log10(x) = log10(x_significand) + x_exponent + // log10(x_significand) = ln(x_significand) / ln(10) + k = mathpow(+x, yn); + e = k == 0 || !isFinite(k) + ? mathfloor(yn * (Math.log('0.' + digitsToString(x.d)) / Math.LN10 + x.e + 1)) + : new Ctor(k + '').e; + + // Exponent estimate may be incorrect e.g. x: 0.999999999999999999, y: 2.29, e: 0, r.e: -1. + + // Overflow/underflow? + if (e > Ctor.maxE + 1 || e < Ctor.minE - 1) return new Ctor(e > 0 ? s / 0 : 0); + + external = false; + Ctor.rounding = x.s = 1; + + // Estimate the extra guard digits needed to ensure five correct rounding digits from + // naturalLogarithm(x). Example of failure without these extra digits (precision: 10): + // new Decimal(2.32456).pow('2087987436534566.46411') + // should be 1.162377823e+764914905173815, but is 1.162355823e+764914905173815 + k = Math.min(12, (e + '').length); + + // r = x^y = exp(y*ln(x)) + r = naturalExponential(y.times(naturalLogarithm(x, pr + k)), pr); + + // r may be Infinity, e.g. (0.9999999999999999).pow(-1e+40) + if (r.d) { + + // Truncate to the required precision plus five rounding digits. + r = finalise(r, pr + 5, 1); + + // If the rounding digits are [49]9999 or [50]0000 increase the precision by 10 and recalculate + // the result. + if (checkRoundingDigits(r.d, pr, rm)) { + e = pr + 10; + + // Truncate to the increased precision plus five rounding digits. + r = finalise(naturalExponential(y.times(naturalLogarithm(x, e + k)), e), e + 5, 1); + + // Check for 14 nines from the 2nd rounding digit (the first rounding digit may be 4 or 9). + if (+digitsToString(r.d).slice(pr + 1, pr + 15) + 1 == 1e14) { + r = finalise(r, pr + 1, 0); + } + } + } + + r.s = s; + external = true; + Ctor.rounding = rm; + + return finalise(r, pr, rm); +}; + + +/* + * Return a string representing the value of this Decimal rounded to `sd` significant digits + * using rounding mode `rounding`. + * + * Return exponential notation if `sd` is less than the number of digits necessary to represent + * the integer part of the value in normal notation. + * + * [sd] {number} Significant digits. Integer, 1 to MAX_DIGITS inclusive. + * [rm] {number} Rounding mode. Integer, 0 to 8 inclusive. + * + */ +P.toPrecision = function (sd, rm) { + var str, + x = this, + Ctor = x.constructor; + + if (sd === void 0) { + str = finiteToString(x, x.e <= Ctor.toExpNeg || x.e >= Ctor.toExpPos); + } else { + checkInt32(sd, 1, MAX_DIGITS); + + if (rm === void 0) rm = Ctor.rounding; + else checkInt32(rm, 0, 8); + + x = finalise(new Ctor(x), sd, rm); + str = finiteToString(x, sd <= x.e || x.e <= Ctor.toExpNeg, sd); + } + + return x.isNeg() && !x.isZero() ? '-' + str : str; +}; + + +/* + * Return a new Decimal whose value is the value of this Decimal rounded to a maximum of `sd` + * significant digits using rounding mode `rm`, or to `precision` and `rounding` respectively if + * omitted. + * + * [sd] {number} Significant digits. Integer, 1 to MAX_DIGITS inclusive. + * [rm] {number} Rounding mode. Integer, 0 to 8 inclusive. + * + * 'toSD() digits out of range: {sd}' + * 'toSD() digits not an integer: {sd}' + * 'toSD() rounding mode not an integer: {rm}' + * 'toSD() rounding mode out of range: {rm}' + * + */ +P.toSignificantDigits = P.toSD = function (sd, rm) { + var x = this, + Ctor = x.constructor; + + if (sd === void 0) { + sd = Ctor.precision; + rm = Ctor.rounding; + } else { + checkInt32(sd, 1, MAX_DIGITS); + + if (rm === void 0) rm = Ctor.rounding; + else checkInt32(rm, 0, 8); + } + + return finalise(new Ctor(x), sd, rm); +}; + + +/* + * Return a string representing the value of this Decimal. + * + * Return exponential notation if this Decimal has a positive exponent equal to or greater than + * `toExpPos`, or a negative exponent equal to or less than `toExpNeg`. + * + */ +P.toString = function () { + var x = this, + Ctor = x.constructor, + str = finiteToString(x, x.e <= Ctor.toExpNeg || x.e >= Ctor.toExpPos); + + return x.isNeg() && !x.isZero() ? '-' + str : str; +}; + + +/* + * Return a new Decimal whose value is the value of this Decimal truncated to a whole number. + * + */ +P.truncated = P.trunc = function () { + return finalise(new this.constructor(this), this.e + 1, 1); +}; + + +/* + * Return a string representing the value of this Decimal. + * Unlike `toString`, negative zero will include the minus sign. + * + */ +P.valueOf = P.toJSON = function () { + var x = this, + Ctor = x.constructor, + str = finiteToString(x, x.e <= Ctor.toExpNeg || x.e >= Ctor.toExpPos); + + return x.isNeg() ? '-' + str : str; +}; + + +// Helper functions for Decimal.prototype (P) and/or Decimal methods, and their callers. + + +/* + * digitsToString P.cubeRoot, P.logarithm, P.squareRoot, P.toFraction, P.toPower, + * finiteToString, naturalExponential, naturalLogarithm + * checkInt32 P.toDecimalPlaces, P.toExponential, P.toFixed, P.toNearest, + * P.toPrecision, P.toSignificantDigits, toStringBinary, random + * checkRoundingDigits P.logarithm, P.toPower, naturalExponential, naturalLogarithm + * convertBase toStringBinary, parseOther + * cos P.cos + * divide P.atanh, P.cubeRoot, P.dividedBy, P.dividedToIntegerBy, + * P.logarithm, P.modulo, P.squareRoot, P.tan, P.tanh, P.toFraction, + * P.toNearest, toStringBinary, naturalExponential, naturalLogarithm, + * taylorSeries, atan2, parseOther + * finalise P.absoluteValue, P.atan, P.atanh, P.ceil, P.cos, P.cosh, + * P.cubeRoot, P.dividedToIntegerBy, P.floor, P.logarithm, P.minus, + * P.modulo, P.negated, P.plus, P.round, P.sin, P.sinh, P.squareRoot, + * P.tan, P.times, P.toDecimalPlaces, P.toExponential, P.toFixed, + * P.toNearest, P.toPower, P.toPrecision, P.toSignificantDigits, + * P.truncated, divide, getLn10, getPi, naturalExponential, + * naturalLogarithm, ceil, floor, round, trunc + * finiteToString P.toExponential, P.toFixed, P.toPrecision, P.toString, P.valueOf, + * toStringBinary + * getBase10Exponent P.minus, P.plus, P.times, parseOther + * getLn10 P.logarithm, naturalLogarithm + * getPi P.acos, P.asin, P.atan, toLessThanHalfPi, atan2 + * getPrecision P.precision, P.toFraction + * getZeroString digitsToString, finiteToString + * intPow P.toPower, parseOther + * isOdd toLessThanHalfPi + * maxOrMin max, min + * naturalExponential P.naturalExponential, P.toPower + * naturalLogarithm P.acosh, P.asinh, P.atanh, P.logarithm, P.naturalLogarithm, + * P.toPower, naturalExponential + * nonFiniteToString finiteToString, toStringBinary + * parseDecimal Decimal + * parseOther Decimal + * sin P.sin + * taylorSeries P.cosh, P.sinh, cos, sin + * toLessThanHalfPi P.cos, P.sin + * toStringBinary P.toBinary, P.toHexadecimal, P.toOctal + * truncate intPow + * + * Throws: P.logarithm, P.precision, P.toFraction, checkInt32, getLn10, getPi, + * naturalLogarithm, config, parseOther, random, Decimal + */ + + +function digitsToString(d) { + var i, k, ws, + indexOfLastWord = d.length - 1, + str = '', + w = d[0]; + + if (indexOfLastWord > 0) { + str += w; + for (i = 1; i < indexOfLastWord; i++) { + ws = d[i] + ''; + k = LOG_BASE - ws.length; + if (k) str += getZeroString(k); + str += ws; + } + + w = d[i]; + ws = w + ''; + k = LOG_BASE - ws.length; + if (k) str += getZeroString(k); + } else if (w === 0) { + return '0'; + } + + // Remove trailing zeros of last w. + for (; w % 10 === 0;) w /= 10; + + return str + w; +} + + +function checkInt32(i, min, max) { + if (i !== ~~i || i < min || i > max) { + throw Error(invalidArgument + i); + } +} + + +/* + * Check 5 rounding digits if `repeating` is null, 4 otherwise. + * `repeating == null` if caller is `log` or `pow`, + * `repeating != null` if caller is `naturalLogarithm` or `naturalExponential`. + */ +function checkRoundingDigits(d, i, rm, repeating) { + var di, k, r, rd; + + // Get the length of the first word of the array d. + for (k = d[0]; k >= 10; k /= 10) --i; + + // Is the rounding digit in the first word of d? + if (--i < 0) { + i += LOG_BASE; + di = 0; + } else { + di = Math.ceil((i + 1) / LOG_BASE); + i %= LOG_BASE; + } + + // i is the index (0 - 6) of the rounding digit. + // E.g. if within the word 3487563 the first rounding digit is 5, + // then i = 4, k = 1000, rd = 3487563 % 1000 = 563 + k = mathpow(10, LOG_BASE - i); + rd = d[di] % k | 0; + + if (repeating == null) { + if (i < 3) { + if (i == 0) rd = rd / 100 | 0; + else if (i == 1) rd = rd / 10 | 0; + r = rm < 4 && rd == 99999 || rm > 3 && rd == 49999 || rd == 50000 || rd == 0; + } else { + r = (rm < 4 && rd + 1 == k || rm > 3 && rd + 1 == k / 2) && + (d[di + 1] / k / 100 | 0) == mathpow(10, i - 2) - 1 || + (rd == k / 2 || rd == 0) && (d[di + 1] / k / 100 | 0) == 0; + } + } else { + if (i < 4) { + if (i == 0) rd = rd / 1000 | 0; + else if (i == 1) rd = rd / 100 | 0; + else if (i == 2) rd = rd / 10 | 0; + r = (repeating || rm < 4) && rd == 9999 || !repeating && rm > 3 && rd == 4999; + } else { + r = ((repeating || rm < 4) && rd + 1 == k || + (!repeating && rm > 3) && rd + 1 == k / 2) && + (d[di + 1] / k / 1000 | 0) == mathpow(10, i - 3) - 1; + } + } + + return r; +} + + +// Convert string of `baseIn` to an array of numbers of `baseOut`. +// Eg. convertBase('255', 10, 16) returns [15, 15]. +// Eg. convertBase('ff', 16, 10) returns [2, 5, 5]. +function convertBase(str, baseIn, baseOut) { + var j, + arr = [0], + arrL, + i = 0, + strL = str.length; + + for (; i < strL;) { + for (arrL = arr.length; arrL--;) arr[arrL] *= baseIn; + arr[0] += NUMERALS.indexOf(str.charAt(i++)); + for (j = 0; j < arr.length; j++) { + if (arr[j] > baseOut - 1) { + if (arr[j + 1] === void 0) arr[j + 1] = 0; + arr[j + 1] += arr[j] / baseOut | 0; + arr[j] %= baseOut; + } + } + } + + return arr.reverse(); +} + + +/* + * cos(x) = 1 - x^2/2! + x^4/4! - ... + * |x| < pi/2 + * + */ +function cosine(Ctor, x) { + var k, len, y; + + if (x.isZero()) return x; + + // Argument reduction: cos(4x) = 8*(cos^4(x) - cos^2(x)) + 1 + // i.e. cos(x) = 8*(cos^4(x/4) - cos^2(x/4)) + 1 + + // Estimate the optimum number of times to use the argument reduction. + len = x.d.length; + if (len < 32) { + k = Math.ceil(len / 3); + y = (1 / tinyPow(4, k)).toString(); + } else { + k = 16; + y = '2.3283064365386962890625e-10'; + } + + Ctor.precision += k; + + x = taylorSeries(Ctor, 1, x.times(y), new Ctor(1)); + + // Reverse argument reduction + for (var i = k; i--;) { + var cos2x = x.times(x); + x = cos2x.times(cos2x).minus(cos2x).times(8).plus(1); + } + + Ctor.precision -= k; + + return x; +} + + +/* + * Perform division in the specified base. + */ +var divide = (function () { + + // Assumes non-zero x and k, and hence non-zero result. + function multiplyInteger(x, k, base) { + var temp, + carry = 0, + i = x.length; + + for (x = x.slice(); i--;) { + temp = x[i] * k + carry; + x[i] = temp % base | 0; + carry = temp / base | 0; + } + + if (carry) x.unshift(carry); + + return x; + } + + function compare(a, b, aL, bL) { + var i, r; + + if (aL != bL) { + r = aL > bL ? 1 : -1; + } else { + for (i = r = 0; i < aL; i++) { + if (a[i] != b[i]) { + r = a[i] > b[i] ? 1 : -1; + break; + } + } + } + + return r; + } + + function subtract(a, b, aL, base) { + var i = 0; + + // Subtract b from a. + for (; aL--;) { + a[aL] -= i; + i = a[aL] < b[aL] ? 1 : 0; + a[aL] = i * base + a[aL] - b[aL]; + } + + // Remove leading zeros. + for (; !a[0] && a.length > 1;) a.shift(); + } + + return function (x, y, pr, rm, dp, base) { + var cmp, e, i, k, logBase, more, prod, prodL, q, qd, rem, remL, rem0, sd, t, xi, xL, yd0, + yL, yz, + Ctor = x.constructor, + sign = x.s == y.s ? 1 : -1, + xd = x.d, + yd = y.d; + + // Either NaN, Infinity or 0? + if (!xd || !xd[0] || !yd || !yd[0]) { + + return new Ctor(// Return NaN if either NaN, or both Infinity or 0. + !x.s || !y.s || (xd ? yd && xd[0] == yd[0] : !yd) ? NaN : + + // Return ±0 if x is 0 or y is ±Infinity, or return ±Infinity as y is 0. + xd && xd[0] == 0 || !yd ? sign * 0 : sign / 0); + } + + if (base) { + logBase = 1; + e = x.e - y.e; + } else { + base = BASE; + logBase = LOG_BASE; + e = mathfloor(x.e / logBase) - mathfloor(y.e / logBase); + } + + yL = yd.length; + xL = xd.length; + q = new Ctor(sign); + qd = q.d = []; + + // Result exponent may be one less than e. + // The digit array of a Decimal from toStringBinary may have trailing zeros. + for (i = 0; yd[i] == (xd[i] || 0); i++); + + if (yd[i] > (xd[i] || 0)) e--; + + if (pr == null) { + sd = pr = Ctor.precision; + rm = Ctor.rounding; + } else if (dp) { + sd = pr + (x.e - y.e) + 1; + } else { + sd = pr; + } + + if (sd < 0) { + qd.push(1); + more = true; + } else { + + // Convert precision in number of base 10 digits to base 1e7 digits. + sd = sd / logBase + 2 | 0; + i = 0; + + // divisor < 1e7 + if (yL == 1) { + k = 0; + yd = yd[0]; + sd++; + + // k is the carry. + for (; (i < xL || k) && sd--; i++) { + t = k * base + (xd[i] || 0); + qd[i] = t / yd | 0; + k = t % yd | 0; + } + + more = k || i < xL; + + // divisor >= 1e7 + } else { + + // Normalise xd and yd so highest order digit of yd is >= base/2 + k = base / (yd[0] + 1) | 0; + + if (k > 1) { + yd = multiplyInteger(yd, k, base); + xd = multiplyInteger(xd, k, base); + yL = yd.length; + xL = xd.length; + } + + xi = yL; + rem = xd.slice(0, yL); + remL = rem.length; + + // Add zeros to make remainder as long as divisor. + for (; remL < yL;) rem[remL++] = 0; + + yz = yd.slice(); + yz.unshift(0); + yd0 = yd[0]; + + if (yd[1] >= base / 2) ++yd0; + + do { + k = 0; + + // Compare divisor and remainder. + cmp = compare(yd, rem, yL, remL); + + // If divisor < remainder. + if (cmp < 0) { + + // Calculate trial digit, k. + rem0 = rem[0]; + if (yL != remL) rem0 = rem0 * base + (rem[1] || 0); + + // k will be how many times the divisor goes into the current remainder. + k = rem0 / yd0 | 0; + + // Algorithm: + // 1. product = divisor * trial digit (k) + // 2. if product > remainder: product -= divisor, k-- + // 3. remainder -= product + // 4. if product was < remainder at 2: + // 5. compare new remainder and divisor + // 6. If remainder > divisor: remainder -= divisor, k++ + + if (k > 1) { + if (k >= base) k = base - 1; + + // product = divisor * trial digit. + prod = multiplyInteger(yd, k, base); + prodL = prod.length; + remL = rem.length; + + // Compare product and remainder. + cmp = compare(prod, rem, prodL, remL); + + // product > remainder. + if (cmp == 1) { + k--; + + // Subtract divisor from product. + subtract(prod, yL < prodL ? yz : yd, prodL, base); + } + } else { + + // cmp is -1. + // If k is 0, there is no need to compare yd and rem again below, so change cmp to 1 + // to avoid it. If k is 1 there is a need to compare yd and rem again below. + if (k == 0) cmp = k = 1; + prod = yd.slice(); + } + + prodL = prod.length; + if (prodL < remL) prod.unshift(0); + + // Subtract product from remainder. + subtract(rem, prod, remL, base); + + // If product was < previous remainder. + if (cmp == -1) { + remL = rem.length; + + // Compare divisor and new remainder. + cmp = compare(yd, rem, yL, remL); + + // If divisor < new remainder, subtract divisor from remainder. + if (cmp < 1) { + k++; + + // Subtract divisor from remainder. + subtract(rem, yL < remL ? yz : yd, remL, base); + } + } + + remL = rem.length; + } else if (cmp === 0) { + k++; + rem = [0]; + } // if cmp === 1, k will be 0 + + // Add the next digit, k, to the result array. + qd[i++] = k; + + // Update the remainder. + if (cmp && rem[0]) { + rem[remL++] = xd[xi] || 0; + } else { + rem = [xd[xi]]; + remL = 1; + } + + } while ((xi++ < xL || rem[0] !== void 0) && sd--); + + more = rem[0] !== void 0; + } + + // Leading zero? + if (!qd[0]) qd.shift(); + } + + // logBase is 1 when divide is being used for base conversion. + if (logBase == 1) { + q.e = e; + inexact = more; + } else { + + // To calculate q.e, first get the number of digits of qd[0]. + for (i = 1, k = qd[0]; k >= 10; k /= 10) i++; + q.e = i + e * logBase - 1; + + finalise(q, dp ? pr + q.e + 1 : pr, rm, more); + } + + return q; + }; +})(); + + +/* + * Round `x` to `sd` significant digits using rounding mode `rm`. + * Check for over/under-flow. + */ + function finalise(x, sd, rm, isTruncated) { + var digits, i, j, k, rd, roundUp, w, xd, xdi, + Ctor = x.constructor; + + // Don't round if sd is null or undefined. + out: if (sd != null) { + xd = x.d; + + // Infinity/NaN. + if (!xd) return x; + + // rd: the rounding digit, i.e. the digit after the digit that may be rounded up. + // w: the word of xd containing rd, a base 1e7 number. + // xdi: the index of w within xd. + // digits: the number of digits of w. + // i: what would be the index of rd within w if all the numbers were 7 digits long (i.e. if + // they had leading zeros) + // j: if > 0, the actual index of rd within w (if < 0, rd is a leading zero). + + // Get the length of the first word of the digits array xd. + for (digits = 1, k = xd[0]; k >= 10; k /= 10) digits++; + i = sd - digits; + + // Is the rounding digit in the first word of xd? + if (i < 0) { + i += LOG_BASE; + j = sd; + w = xd[xdi = 0]; + + // Get the rounding digit at index j of w. + rd = w / mathpow(10, digits - j - 1) % 10 | 0; + } else { + xdi = Math.ceil((i + 1) / LOG_BASE); + k = xd.length; + if (xdi >= k) { + if (isTruncated) { + + // Needed by `naturalExponential`, `naturalLogarithm` and `squareRoot`. + for (; k++ <= xdi;) xd.push(0); + w = rd = 0; + digits = 1; + i %= LOG_BASE; + j = i - LOG_BASE + 1; + } else { + break out; + } + } else { + w = k = xd[xdi]; + + // Get the number of digits of w. + for (digits = 1; k >= 10; k /= 10) digits++; + + // Get the index of rd within w. + i %= LOG_BASE; + + // Get the index of rd within w, adjusted for leading zeros. + // The number of leading zeros of w is given by LOG_BASE - digits. + j = i - LOG_BASE + digits; + + // Get the rounding digit at index j of w. + rd = j < 0 ? 0 : w / mathpow(10, digits - j - 1) % 10 | 0; + } + } + + // Are there any non-zero digits after the rounding digit? + isTruncated = isTruncated || sd < 0 || + xd[xdi + 1] !== void 0 || (j < 0 ? w : w % mathpow(10, digits - j - 1)); + + // The expression `w % mathpow(10, digits - j - 1)` returns all the digits of w to the right + // of the digit at (left-to-right) index j, e.g. if w is 908714 and j is 2, the expression + // will give 714. + + roundUp = rm < 4 + ? (rd || isTruncated) && (rm == 0 || rm == (x.s < 0 ? 3 : 2)) + : rd > 5 || rd == 5 && (rm == 4 || isTruncated || rm == 6 && + + // Check whether the digit to the left of the rounding digit is odd. + ((i > 0 ? j > 0 ? w / mathpow(10, digits - j) : 0 : xd[xdi - 1]) % 10) & 1 || + rm == (x.s < 0 ? 8 : 7)); + + if (sd < 1 || !xd[0]) { + xd.length = 0; + if (roundUp) { + + // Convert sd to decimal places. + sd -= x.e + 1; + + // 1, 0.1, 0.01, 0.001, 0.0001 etc. + xd[0] = mathpow(10, (LOG_BASE - sd % LOG_BASE) % LOG_BASE); + x.e = -sd || 0; + } else { + + // Zero. + xd[0] = x.e = 0; + } + + return x; + } + + // Remove excess digits. + if (i == 0) { + xd.length = xdi; + k = 1; + xdi--; + } else { + xd.length = xdi + 1; + k = mathpow(10, LOG_BASE - i); + + // E.g. 56700 becomes 56000 if 7 is the rounding digit. + // j > 0 means i > number of leading zeros of w. + xd[xdi] = j > 0 ? (w / mathpow(10, digits - j) % mathpow(10, j) | 0) * k : 0; + } + + if (roundUp) { + for (;;) { + + // Is the digit to be rounded up in the first word of xd? + if (xdi == 0) { + + // i will be the length of xd[0] before k is added. + for (i = 1, j = xd[0]; j >= 10; j /= 10) i++; + j = xd[0] += k; + for (k = 1; j >= 10; j /= 10) k++; + + // if i != k the length has increased. + if (i != k) { + x.e++; + if (xd[0] == BASE) xd[0] = 1; + } + + break; + } else { + xd[xdi] += k; + if (xd[xdi] != BASE) break; + xd[xdi--] = 0; + k = 1; + } + } + } + + // Remove trailing zeros. + for (i = xd.length; xd[--i] === 0;) xd.pop(); + } + + if (external) { + + // Overflow? + if (x.e > Ctor.maxE) { + + // Infinity. + x.d = null; + x.e = NaN; + + // Underflow? + } else if (x.e < Ctor.minE) { + + // Zero. + x.e = 0; + x.d = [0]; + // Ctor.underflow = true; + } // else Ctor.underflow = false; + } + + return x; +} + + +function finiteToString(x, isExp, sd) { + if (!x.isFinite()) return nonFiniteToString(x); + var k, + e = x.e, + str = digitsToString(x.d), + len = str.length; + + if (isExp) { + if (sd && (k = sd - len) > 0) { + str = str.charAt(0) + '.' + str.slice(1) + getZeroString(k); + } else if (len > 1) { + str = str.charAt(0) + '.' + str.slice(1); + } + + str = str + (x.e < 0 ? 'e' : 'e+') + x.e; + } else if (e < 0) { + str = '0.' + getZeroString(-e - 1) + str; + if (sd && (k = sd - len) > 0) str += getZeroString(k); + } else if (e >= len) { + str += getZeroString(e + 1 - len); + if (sd && (k = sd - e - 1) > 0) str = str + '.' + getZeroString(k); + } else { + if ((k = e + 1) < len) str = str.slice(0, k) + '.' + str.slice(k); + if (sd && (k = sd - len) > 0) { + if (e + 1 === len) str += '.'; + str += getZeroString(k); + } + } + + return str; +} + + +// Calculate the base 10 exponent from the base 1e7 exponent. +function getBase10Exponent(digits, e) { + var w = digits[0]; + + // Add the number of digits of the first word of the digits array. + for ( e *= LOG_BASE; w >= 10; w /= 10) e++; + return e; +} + + +function getLn10(Ctor, sd, pr) { + if (sd > LN10_PRECISION) { + + // Reset global state in case the exception is caught. + external = true; + if (pr) Ctor.precision = pr; + throw Error(precisionLimitExceeded); + } + return finalise(new Ctor(LN10), sd, 1, true); +} + + +function getPi(Ctor, sd, rm) { + if (sd > PI_PRECISION) throw Error(precisionLimitExceeded); + return finalise(new Ctor(PI), sd, rm, true); +} + + +function getPrecision(digits) { + var w = digits.length - 1, + len = w * LOG_BASE + 1; + + w = digits[w]; + + // If non-zero... + if (w) { + + // Subtract the number of trailing zeros of the last word. + for (; w % 10 == 0; w /= 10) len--; + + // Add the number of digits of the first word. + for (w = digits[0]; w >= 10; w /= 10) len++; + } + + return len; +} + + +function getZeroString(k) { + var zs = ''; + for (; k--;) zs += '0'; + return zs; +} + + +/* + * Return a new Decimal whose value is the value of Decimal `x` to the power `n`, where `n` is an + * integer of type number. + * + * Implements 'exponentiation by squaring'. Called by `pow` and `parseOther`. + * + */ +function intPow(Ctor, x, n, pr) { + var isTruncated, + r = new Ctor(1), + + // Max n of 9007199254740991 takes 53 loop iterations. + // Maximum digits array length; leaves [28, 34] guard digits. + k = Math.ceil(pr / LOG_BASE + 4); + + external = false; + + for (;;) { + if (n % 2) { + r = r.times(x); + if (truncate(r.d, k)) isTruncated = true; + } + + n = mathfloor(n / 2); + if (n === 0) { + + // To ensure correct rounding when r.d is truncated, increment the last word if it is zero. + n = r.d.length - 1; + if (isTruncated && r.d[n] === 0) ++r.d[n]; + break; + } + + x = x.times(x); + truncate(x.d, k); + } + + external = true; + + return r; +} + + +function isOdd(n) { + return n.d[n.d.length - 1] & 1; +} + + +/* + * Handle `max` (`n` is -1) and `min` (`n` is 1). + */ +function maxOrMin(Ctor, args, n) { + var k, y, + x = new Ctor(args[0]), + i = 0; + + for (; ++i < args.length;) { + y = new Ctor(args[i]); + + // NaN? + if (!y.s) { + x = y; + break; + } + + k = x.cmp(y); + + if (k === n || k === 0 && x.s === n) { + x = y; + } + } + + return x; +} + + +/* + * Return a new Decimal whose value is the natural exponential of `x` rounded to `sd` significant + * digits. + * + * Taylor/Maclaurin series. + * + * exp(x) = x^0/0! + x^1/1! + x^2/2! + x^3/3! + ... + * + * Argument reduction: + * Repeat x = x / 32, k += 5, until |x| < 0.1 + * exp(x) = exp(x / 2^k)^(2^k) + * + * Previously, the argument was initially reduced by + * exp(x) = exp(r) * 10^k where r = x - k * ln10, k = floor(x / ln10) + * to first put r in the range [0, ln10], before dividing by 32 until |x| < 0.1, but this was + * found to be slower than just dividing repeatedly by 32 as above. + * + * Max integer argument: exp('20723265836946413') = 6.3e+9000000000000000 + * Min integer argument: exp('-20723265836946411') = 1.2e-9000000000000000 + * (Math object integer min/max: Math.exp(709) = 8.2e+307, Math.exp(-745) = 5e-324) + * + * exp(Infinity) = Infinity + * exp(-Infinity) = 0 + * exp(NaN) = NaN + * exp(±0) = 1 + * + * exp(x) is non-terminating for any finite, non-zero x. + * + * The result will always be correctly rounded. + * + */ +function naturalExponential(x, sd) { + var denominator, guard, j, pow, sum, t, wpr, + rep = 0, + i = 0, + k = 0, + Ctor = x.constructor, + rm = Ctor.rounding, + pr = Ctor.precision; + + // 0/NaN/Infinity? + if (!x.d || !x.d[0] || x.e > 17) { + + return new Ctor(x.d + ? !x.d[0] ? 1 : x.s < 0 ? 0 : 1 / 0 + : x.s ? x.s < 0 ? 0 : x : 0 / 0); + } + + if (sd == null) { + external = false; + wpr = pr; + } else { + wpr = sd; + } + + t = new Ctor(0.03125); + + // while abs(x) >= 0.1 + while (x.e > -2) { + + // x = x / 2^5 + x = x.times(t); + k += 5; + } + + // Use 2 * log10(2^k) + 5 (empirically derived) to estimate the increase in precision + // necessary to ensure the first 4 rounding digits are correct. + guard = Math.log(mathpow(2, k)) / Math.LN10 * 2 + 5 | 0; + wpr += guard; + denominator = pow = sum = new Ctor(1); + Ctor.precision = wpr; + + for (;;) { + pow = finalise(pow.times(x), wpr, 1); + denominator = denominator.times(++i); + t = sum.plus(divide(pow, denominator, wpr, 1)); + + if (digitsToString(t.d).slice(0, wpr) === digitsToString(sum.d).slice(0, wpr)) { + j = k; + while (j--) sum = finalise(sum.times(sum), wpr, 1); + + // Check to see if the first 4 rounding digits are [49]999. + // If so, repeat the summation with a higher precision, otherwise + // e.g. with precision: 18, rounding: 1 + // exp(18.404272462595034083567793919843761) = 98372560.1229999999 (should be 98372560.123) + // `wpr - guard` is the index of first rounding digit. + if (sd == null) { + + if (rep < 3 && checkRoundingDigits(sum.d, wpr - guard, rm, rep)) { + Ctor.precision = wpr += 10; + denominator = pow = t = new Ctor(1); + i = 0; + rep++; + } else { + return finalise(sum, Ctor.precision = pr, rm, external = true); + } + } else { + Ctor.precision = pr; + return sum; + } + } + + sum = t; + } +} + + +/* + * Return a new Decimal whose value is the natural logarithm of `x` rounded to `sd` significant + * digits. + * + * ln(-n) = NaN + * ln(0) = -Infinity + * ln(-0) = -Infinity + * ln(1) = 0 + * ln(Infinity) = Infinity + * ln(-Infinity) = NaN + * ln(NaN) = NaN + * + * ln(n) (n != 1) is non-terminating. + * + */ +function naturalLogarithm(y, sd) { + var c, c0, denominator, e, numerator, rep, sum, t, wpr, x1, x2, + n = 1, + guard = 10, + x = y, + xd = x.d, + Ctor = x.constructor, + rm = Ctor.rounding, + pr = Ctor.precision; + + // Is x negative or Infinity, NaN, 0 or 1? + if (x.s < 0 || !xd || !xd[0] || !x.e && xd[0] == 1 && xd.length == 1) { + return new Ctor(xd && !xd[0] ? -1 / 0 : x.s != 1 ? NaN : xd ? 0 : x); + } + + if (sd == null) { + external = false; + wpr = pr; + } else { + wpr = sd; + } + + Ctor.precision = wpr += guard; + c = digitsToString(xd); + c0 = c.charAt(0); + + if (Math.abs(e = x.e) < 1.5e15) { + + // Argument reduction. + // The series converges faster the closer the argument is to 1, so using + // ln(a^b) = b * ln(a), ln(a) = ln(a^b) / b + // multiply the argument by itself until the leading digits of the significand are 7, 8, 9, + // 10, 11, 12 or 13, recording the number of multiplications so the sum of the series can + // later be divided by this number, then separate out the power of 10 using + // ln(a*10^b) = ln(a) + b*ln(10). + + // max n is 21 (gives 0.9, 1.0 or 1.1) (9e15 / 21 = 4.2e14). + //while (c0 < 9 && c0 != 1 || c0 == 1 && c.charAt(1) > 1) { + // max n is 6 (gives 0.7 - 1.3) + while (c0 < 7 && c0 != 1 || c0 == 1 && c.charAt(1) > 3) { + x = x.times(y); + c = digitsToString(x.d); + c0 = c.charAt(0); + n++; + } + + e = x.e; + + if (c0 > 1) { + x = new Ctor('0.' + c); + e++; + } else { + x = new Ctor(c0 + '.' + c.slice(1)); + } + } else { + + // The argument reduction method above may result in overflow if the argument y is a massive + // number with exponent >= 1500000000000000 (9e15 / 6 = 1.5e15), so instead recall this + // function using ln(x*10^e) = ln(x) + e*ln(10). + t = getLn10(Ctor, wpr + 2, pr).times(e + ''); + x = naturalLogarithm(new Ctor(c0 + '.' + c.slice(1)), wpr - guard).plus(t); + Ctor.precision = pr; + + return sd == null ? finalise(x, pr, rm, external = true) : x; + } + + // x1 is x reduced to a value near 1. + x1 = x; + + // Taylor series. + // ln(y) = ln((1 + x)/(1 - x)) = 2(x + x^3/3 + x^5/5 + x^7/7 + ...) + // where x = (y - 1)/(y + 1) (|x| < 1) + sum = numerator = x = divide(x.minus(1), x.plus(1), wpr, 1); + x2 = finalise(x.times(x), wpr, 1); + denominator = 3; + + for (;;) { + numerator = finalise(numerator.times(x2), wpr, 1); + t = sum.plus(divide(numerator, new Ctor(denominator), wpr, 1)); + + if (digitsToString(t.d).slice(0, wpr) === digitsToString(sum.d).slice(0, wpr)) { + sum = sum.times(2); + + // Reverse the argument reduction. Check that e is not 0 because, besides preventing an + // unnecessary calculation, -0 + 0 = +0 and to ensure correct rounding -0 needs to stay -0. + if (e !== 0) sum = sum.plus(getLn10(Ctor, wpr + 2, pr).times(e + '')); + sum = divide(sum, new Ctor(n), wpr, 1); + + // Is rm > 3 and the first 4 rounding digits 4999, or rm < 4 (or the summation has + // been repeated previously) and the first 4 rounding digits 9999? + // If so, restart the summation with a higher precision, otherwise + // e.g. with precision: 12, rounding: 1 + // ln(135520028.6126091714265381533) = 18.7246299999 when it should be 18.72463. + // `wpr - guard` is the index of first rounding digit. + if (sd == null) { + if (checkRoundingDigits(sum.d, wpr - guard, rm, rep)) { + Ctor.precision = wpr += guard; + t = numerator = x = divide(x1.minus(1), x1.plus(1), wpr, 1); + x2 = finalise(x.times(x), wpr, 1); + denominator = rep = 1; + } else { + return finalise(sum, Ctor.precision = pr, rm, external = true); + } + } else { + Ctor.precision = pr; + return sum; + } + } + + sum = t; + denominator += 2; + } +} + + +// ±Infinity, NaN. +function nonFiniteToString(x) { + // Unsigned. + return String(x.s * x.s / 0); +} + + +/* + * Parse the value of a new Decimal `x` from string `str`. + */ +function parseDecimal(x, str) { + var e, i, len; + + // TODO BigInt str: no need to check for decimal point, exponential form or leading zeros. + // Decimal point? + if ((e = str.indexOf('.')) > -1) str = str.replace('.', ''); + + // Exponential form? + if ((i = str.search(/e/i)) > 0) { + + // Determine exponent. + if (e < 0) e = i; + e += +str.slice(i + 1); + str = str.substring(0, i); + } else if (e < 0) { + + // Integer. + e = str.length; + } + + // Determine leading zeros. + for (i = 0; str.charCodeAt(i) === 48; i++); + + // Determine trailing zeros. + for (len = str.length; str.charCodeAt(len - 1) === 48; --len); + str = str.slice(i, len); + + if (str) { + len -= i; + x.e = e = e - i - 1; + x.d = []; + + // Transform base + + // e is the base 10 exponent. + // i is where to slice str to get the first word of the digits array. + i = (e + 1) % LOG_BASE; + if (e < 0) i += LOG_BASE; + + if (i < len) { + if (i) x.d.push(+str.slice(0, i)); + for (len -= LOG_BASE; i < len;) x.d.push(+str.slice(i, i += LOG_BASE)); + str = str.slice(i); + i = LOG_BASE - str.length; + } else { + i -= len; + } + + for (; i--;) str += '0'; + x.d.push(+str); + + if (external) { + + // Overflow? + if (x.e > x.constructor.maxE) { + + // Infinity. + x.d = null; + x.e = NaN; + + // Underflow? + } else if (x.e < x.constructor.minE) { + + // Zero. + x.e = 0; + x.d = [0]; + // x.constructor.underflow = true; + } // else x.constructor.underflow = false; + } + } else { + + // Zero. + x.e = 0; + x.d = [0]; + } + + return x; +} + + +/* + * Parse the value of a new Decimal `x` from a string `str`, which is not a decimal value. + */ +function parseOther(x, str) { + var base, Ctor, divisor, i, isFloat, len, p, xd, xe; + + if (str.indexOf('_') > -1) { + str = str.replace(/(\d)_(?=\d)/g, '$1'); + if (isDecimal.test(str)) return parseDecimal(x, str); + } else if (str === 'Infinity' || str === 'NaN') { + if (!+str) x.s = NaN; + x.e = NaN; + x.d = null; + return x; + } + + if (isHex.test(str)) { + base = 16; + str = str.toLowerCase(); + } else if (isBinary.test(str)) { + base = 2; + } else if (isOctal.test(str)) { + base = 8; + } else { + throw Error(invalidArgument + str); + } + + // Is there a binary exponent part? + i = str.search(/p/i); + + if (i > 0) { + p = +str.slice(i + 1); + str = str.substring(2, i); + } else { + str = str.slice(2); + } + + // Convert `str` as an integer then divide the result by `base` raised to a power such that the + // fraction part will be restored. + i = str.indexOf('.'); + isFloat = i >= 0; + Ctor = x.constructor; + + if (isFloat) { + str = str.replace('.', ''); + len = str.length; + i = len - i; + + // log[10](16) = 1.2041... , log[10](88) = 1.9444.... + divisor = intPow(Ctor, new Ctor(base), i, i * 2); + } + + xd = convertBase(str, base, BASE); + xe = xd.length - 1; + + // Remove trailing zeros. + for (i = xe; xd[i] === 0; --i) xd.pop(); + if (i < 0) return new Ctor(x.s * 0); + x.e = getBase10Exponent(xd, xe); + x.d = xd; + external = false; + + // At what precision to perform the division to ensure exact conversion? + // maxDecimalIntegerPartDigitCount = ceil(log[10](b) * otherBaseIntegerPartDigitCount) + // log[10](2) = 0.30103, log[10](8) = 0.90309, log[10](16) = 1.20412 + // E.g. ceil(1.2 * 3) = 4, so up to 4 decimal digits are needed to represent 3 hex int digits. + // maxDecimalFractionPartDigitCount = {Hex:4|Oct:3|Bin:1} * otherBaseFractionPartDigitCount + // Therefore using 4 * the number of digits of str will always be enough. + if (isFloat) x = divide(x, divisor, len * 4); + + // Multiply by the binary exponent part if present. + if (p) x = x.times(Math.abs(p) < 54 ? mathpow(2, p) : Decimal.pow(2, p)); + external = true; + + return x; +} + + +/* + * sin(x) = x - x^3/3! + x^5/5! - ... + * |x| < pi/2 + * + */ +function sine(Ctor, x) { + var k, + len = x.d.length; + + if (len < 3) { + return x.isZero() ? x : taylorSeries(Ctor, 2, x, x); + } + + // Argument reduction: sin(5x) = 16*sin^5(x) - 20*sin^3(x) + 5*sin(x) + // i.e. sin(x) = 16*sin^5(x/5) - 20*sin^3(x/5) + 5*sin(x/5) + // and sin(x) = sin(x/5)(5 + sin^2(x/5)(16sin^2(x/5) - 20)) + + // Estimate the optimum number of times to use the argument reduction. + k = 1.4 * Math.sqrt(len); + k = k > 16 ? 16 : k | 0; + + x = x.times(1 / tinyPow(5, k)); + x = taylorSeries(Ctor, 2, x, x); + + // Reverse argument reduction + var sin2_x, + d5 = new Ctor(5), + d16 = new Ctor(16), + d20 = new Ctor(20); + for (; k--;) { + sin2_x = x.times(x); + x = x.times(d5.plus(sin2_x.times(d16.times(sin2_x).minus(d20)))); + } + + return x; +} + + +// Calculate Taylor series for `cos`, `cosh`, `sin` and `sinh`. +function taylorSeries(Ctor, n, x, y, isHyperbolic) { + var j, t, u, x2, + i = 1, + pr = Ctor.precision, + k = Math.ceil(pr / LOG_BASE); + + external = false; + x2 = x.times(x); + u = new Ctor(y); + + for (;;) { + t = divide(u.times(x2), new Ctor(n++ * n++), pr, 1); + u = isHyperbolic ? y.plus(t) : y.minus(t); + y = divide(t.times(x2), new Ctor(n++ * n++), pr, 1); + t = u.plus(y); + + if (t.d[k] !== void 0) { + for (j = k; t.d[j] === u.d[j] && j--;); + if (j == -1) break; + } + + j = u; + u = y; + y = t; + t = j; + i++; + } + + external = true; + t.d.length = k + 1; + + return t; +} + + +// Exponent e must be positive and non-zero. +function tinyPow(b, e) { + var n = b; + while (--e) n *= b; + return n; +} + + +// Return the absolute value of `x` reduced to less than or equal to half pi. +function toLessThanHalfPi(Ctor, x) { + var t, + isNeg = x.s < 0, + pi = getPi(Ctor, Ctor.precision, 1), + halfPi = pi.times(0.5); + + x = x.abs(); + + if (x.lte(halfPi)) { + quadrant = isNeg ? 4 : 1; + return x; + } + + t = x.divToInt(pi); + + if (t.isZero()) { + quadrant = isNeg ? 3 : 2; + } else { + x = x.minus(t.times(pi)); + + // 0 <= x < pi + if (x.lte(halfPi)) { + quadrant = isOdd(t) ? (isNeg ? 2 : 3) : (isNeg ? 4 : 1); + return x; + } + + quadrant = isOdd(t) ? (isNeg ? 1 : 4) : (isNeg ? 3 : 2); + } + + return x.minus(pi).abs(); +} + + +/* + * Return the value of Decimal `x` as a string in base `baseOut`. + * + * If the optional `sd` argument is present include a binary exponent suffix. + */ +function toStringBinary(x, baseOut, sd, rm) { + var base, e, i, k, len, roundUp, str, xd, y, + Ctor = x.constructor, + isExp = sd !== void 0; + + if (isExp) { + checkInt32(sd, 1, MAX_DIGITS); + if (rm === void 0) rm = Ctor.rounding; + else checkInt32(rm, 0, 8); + } else { + sd = Ctor.precision; + rm = Ctor.rounding; + } + + if (!x.isFinite()) { + str = nonFiniteToString(x); + } else { + str = finiteToString(x); + i = str.indexOf('.'); + + // Use exponential notation according to `toExpPos` and `toExpNeg`? No, but if required: + // maxBinaryExponent = floor((decimalExponent + 1) * log[2](10)) + // minBinaryExponent = floor(decimalExponent * log[2](10)) + // log[2](10) = 3.321928094887362347870319429489390175864 + + if (isExp) { + base = 2; + if (baseOut == 16) { + sd = sd * 4 - 3; + } else if (baseOut == 8) { + sd = sd * 3 - 2; + } + } else { + base = baseOut; + } + + // Convert the number as an integer then divide the result by its base raised to a power such + // that the fraction part will be restored. + + // Non-integer. + if (i >= 0) { + str = str.replace('.', ''); + y = new Ctor(1); + y.e = str.length - i; + y.d = convertBase(finiteToString(y), 10, base); + y.e = y.d.length; + } + + xd = convertBase(str, 10, base); + e = len = xd.length; + + // Remove trailing zeros. + for (; xd[--len] == 0;) xd.pop(); + + if (!xd[0]) { + str = isExp ? '0p+0' : '0'; + } else { + if (i < 0) { + e--; + } else { + x = new Ctor(x); + x.d = xd; + x.e = e; + x = divide(x, y, sd, rm, 0, base); + xd = x.d; + e = x.e; + roundUp = inexact; + } + + // The rounding digit, i.e. the digit after the digit that may be rounded up. + i = xd[sd]; + k = base / 2; + roundUp = roundUp || xd[sd + 1] !== void 0; + + roundUp = rm < 4 + ? (i !== void 0 || roundUp) && (rm === 0 || rm === (x.s < 0 ? 3 : 2)) + : i > k || i === k && (rm === 4 || roundUp || rm === 6 && xd[sd - 1] & 1 || + rm === (x.s < 0 ? 8 : 7)); + + xd.length = sd; + + if (roundUp) { + + // Rounding up may mean the previous digit has to be rounded up and so on. + for (; ++xd[--sd] > base - 1;) { + xd[sd] = 0; + if (!sd) { + ++e; + xd.unshift(1); + } + } + } + + // Determine trailing zeros. + for (len = xd.length; !xd[len - 1]; --len); + + // E.g. [4, 11, 15] becomes 4bf. + for (i = 0, str = ''; i < len; i++) str += NUMERALS.charAt(xd[i]); + + // Add binary exponent suffix? + if (isExp) { + if (len > 1) { + if (baseOut == 16 || baseOut == 8) { + i = baseOut == 16 ? 4 : 3; + for (--len; len % i; len++) str += '0'; + xd = convertBase(str, base, baseOut); + for (len = xd.length; !xd[len - 1]; --len); + + // xd[0] will always be be 1 + for (i = 1, str = '1.'; i < len; i++) str += NUMERALS.charAt(xd[i]); + } else { + str = str.charAt(0) + '.' + str.slice(1); + } + } + + str = str + (e < 0 ? 'p' : 'p+') + e; + } else if (e < 0) { + for (; ++e;) str = '0' + str; + str = '0.' + str; + } else { + if (++e > len) for (e -= len; e-- ;) str += '0'; + else if (e < len) str = str.slice(0, e) + '.' + str.slice(e); + } + } + + str = (baseOut == 16 ? '0x' : baseOut == 2 ? '0b' : baseOut == 8 ? '0o' : '') + str; + } + + return x.s < 0 ? '-' + str : str; +} + + +// Does not strip trailing zeros. +function truncate(arr, len) { + if (arr.length > len) { + arr.length = len; + return true; + } +} + + +// Decimal methods + + +/* + * abs + * acos + * acosh + * add + * asin + * asinh + * atan + * atanh + * atan2 + * cbrt + * ceil + * clamp + * clone + * config + * cos + * cosh + * div + * exp + * floor + * hypot + * ln + * log + * log2 + * log10 + * max + * min + * mod + * mul + * pow + * random + * round + * set + * sign + * sin + * sinh + * sqrt + * sub + * sum + * tan + * tanh + * trunc + */ + + +/* + * Return a new Decimal whose value is the absolute value of `x`. + * + * x {number|string|bigint|Decimal} + * + */ +function abs(x) { + return new this(x).abs(); +} + + +/* + * Return a new Decimal whose value is the arccosine in radians of `x`. + * + * x {number|string|bigint|Decimal} + * + */ +function acos(x) { + return new this(x).acos(); +} + + +/* + * Return a new Decimal whose value is the inverse of the hyperbolic cosine of `x`, rounded to + * `precision` significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} A value in radians. + * + */ +function acosh(x) { + return new this(x).acosh(); +} + + +/* + * Return a new Decimal whose value is the sum of `x` and `y`, rounded to `precision` significant + * digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * y {number|string|bigint|Decimal} + * + */ +function add(x, y) { + return new this(x).plus(y); +} + + +/* + * Return a new Decimal whose value is the arcsine in radians of `x`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * + */ +function asin(x) { + return new this(x).asin(); +} + + +/* + * Return a new Decimal whose value is the inverse of the hyperbolic sine of `x`, rounded to + * `precision` significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} A value in radians. + * + */ +function asinh(x) { + return new this(x).asinh(); +} + + +/* + * Return a new Decimal whose value is the arctangent in radians of `x`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * + */ +function atan(x) { + return new this(x).atan(); +} + + +/* + * Return a new Decimal whose value is the inverse of the hyperbolic tangent of `x`, rounded to + * `precision` significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} A value in radians. + * + */ +function atanh(x) { + return new this(x).atanh(); +} + + +/* + * Return a new Decimal whose value is the arctangent in radians of `y/x` in the range -pi to pi + * (inclusive), rounded to `precision` significant digits using rounding mode `rounding`. + * + * Domain: [-Infinity, Infinity] + * Range: [-pi, pi] + * + * y {number|string|bigint|Decimal} The y-coordinate. + * x {number|string|bigint|Decimal} The x-coordinate. + * + * atan2(±0, -0) = ±pi + * atan2(±0, +0) = ±0 + * atan2(±0, -x) = ±pi for x > 0 + * atan2(±0, x) = ±0 for x > 0 + * atan2(-y, ±0) = -pi/2 for y > 0 + * atan2(y, ±0) = pi/2 for y > 0 + * atan2(±y, -Infinity) = ±pi for finite y > 0 + * atan2(±y, +Infinity) = ±0 for finite y > 0 + * atan2(±Infinity, x) = ±pi/2 for finite x + * atan2(±Infinity, -Infinity) = ±3*pi/4 + * atan2(±Infinity, +Infinity) = ±pi/4 + * atan2(NaN, x) = NaN + * atan2(y, NaN) = NaN + * + */ +function atan2(y, x) { + y = new this(y); + x = new this(x); + var r, + pr = this.precision, + rm = this.rounding, + wpr = pr + 4; + + // Either NaN + if (!y.s || !x.s) { + r = new this(NaN); + + // Both ±Infinity + } else if (!y.d && !x.d) { + r = getPi(this, wpr, 1).times(x.s > 0 ? 0.25 : 0.75); + r.s = y.s; + + // x is ±Infinity or y is ±0 + } else if (!x.d || y.isZero()) { + r = x.s < 0 ? getPi(this, pr, rm) : new this(0); + r.s = y.s; + + // y is ±Infinity or x is ±0 + } else if (!y.d || x.isZero()) { + r = getPi(this, wpr, 1).times(0.5); + r.s = y.s; + + // Both non-zero and finite + } else if (x.s < 0) { + this.precision = wpr; + this.rounding = 1; + r = this.atan(divide(y, x, wpr, 1)); + x = getPi(this, wpr, 1); + this.precision = pr; + this.rounding = rm; + r = y.s < 0 ? r.minus(x) : r.plus(x); + } else { + r = this.atan(divide(y, x, wpr, 1)); + } + + return r; +} + + +/* + * Return a new Decimal whose value is the cube root of `x`, rounded to `precision` significant + * digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * + */ +function cbrt(x) { + return new this(x).cbrt(); +} + + +/* + * Return a new Decimal whose value is `x` rounded to an integer using `ROUND_CEIL`. + * + * x {number|string|bigint|Decimal} + * + */ +function ceil(x) { + return finalise(x = new this(x), x.e + 1, 2); +} + + +/* + * Return a new Decimal whose value is `x` clamped to the range delineated by `min` and `max`. + * + * x {number|string|bigint|Decimal} + * min {number|string|bigint|Decimal} + * max {number|string|bigint|Decimal} + * + */ +function clamp(x, min, max) { + return new this(x).clamp(min, max); +} + + +/* + * Configure global settings for a Decimal constructor. + * + * `obj` is an object with one or more of the following properties, + * + * precision {number} + * rounding {number} + * toExpNeg {number} + * toExpPos {number} + * maxE {number} + * minE {number} + * modulo {number} + * crypto {boolean|number} + * defaults {true} + * + * E.g. Decimal.config({ precision: 20, rounding: 4 }) + * + */ +function config(obj) { + if (!obj || typeof obj !== 'object') throw Error(decimalError + 'Object expected'); + var i, p, v, + useDefaults = obj.defaults === true, + ps = [ + 'precision', 1, MAX_DIGITS, + 'rounding', 0, 8, + 'toExpNeg', -EXP_LIMIT, 0, + 'toExpPos', 0, EXP_LIMIT, + 'maxE', 0, EXP_LIMIT, + 'minE', -EXP_LIMIT, 0, + 'modulo', 0, 9 + ]; + + for (i = 0; i < ps.length; i += 3) { + if (p = ps[i], useDefaults) this[p] = DEFAULTS[p]; + if ((v = obj[p]) !== void 0) { + if (mathfloor(v) === v && v >= ps[i + 1] && v <= ps[i + 2]) this[p] = v; + else throw Error(invalidArgument + p + ': ' + v); + } + } + + if (p = 'crypto', useDefaults) this[p] = DEFAULTS[p]; + if ((v = obj[p]) !== void 0) { + if (v === true || v === false || v === 0 || v === 1) { + if (v) { + if (typeof crypto != 'undefined' && crypto && + (crypto.getRandomValues || crypto.randomBytes)) { + this[p] = true; + } else { + throw Error(cryptoUnavailable); + } + } else { + this[p] = false; + } + } else { + throw Error(invalidArgument + p + ': ' + v); + } + } + + return this; +} + + +/* + * Return a new Decimal whose value is the cosine of `x`, rounded to `precision` significant + * digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} A value in radians. + * + */ +function cos(x) { + return new this(x).cos(); +} + + +/* + * Return a new Decimal whose value is the hyperbolic cosine of `x`, rounded to precision + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} A value in radians. + * + */ +function cosh(x) { + return new this(x).cosh(); +} + + +/* + * Create and return a Decimal constructor with the same configuration properties as this Decimal + * constructor. + * + */ +function clone(obj) { + var i, p, ps; + + /* + * The Decimal constructor and exported function. + * Return a new Decimal instance. + * + * v {number|string|bigint|Decimal} A numeric value. + * + */ + function Decimal(v) { + var e, i, t, + x = this; + + // Decimal called without new. + if (!(x instanceof Decimal)) return new Decimal(v); + + // Retain a reference to this Decimal constructor, and shadow Decimal.prototype.constructor + // which points to Object. + x.constructor = Decimal; + + if (isDecimalInstance(v)) { + x.s = v.s; + + if (external) { + if (!v.d || v.e > Decimal.maxE) { + + // Infinity. + x.e = NaN; + x.d = null; + } else if (v.e < Decimal.minE) { + + // Zero. + x.e = 0; + x.d = [0]; + } else { + x.e = v.e; + x.d = v.d.slice(); + } + } else { + x.e = v.e; + x.d = v.d ? v.d.slice() : v.d; + } + + return; + } + + t = typeof v; + + if (t === 'number') { + if (v === 0) { + x.s = 1 / v < 0 ? -1 : 1; + x.e = 0; + x.d = [0]; + return; + } + + if (v < 0) { + v = -v; + x.s = -1; + } else { + x.s = 1; + } + + // Fast path for small integers. + if (v === ~~v && v < 1e7) { + for (e = 0, i = v; i >= 10; i /= 10) e++; + + if (external) { + if (e > Decimal.maxE) { + x.e = NaN; + x.d = null; + } else if (e < Decimal.minE) { + x.e = 0; + x.d = [0]; + } else { + x.e = e; + x.d = [v]; + } + } else { + x.e = e; + x.d = [v]; + } + + return; + } + + // Infinity or NaN? + if (v * 0 !== 0) { + if (!v) x.s = NaN; + x.e = NaN; + x.d = null; + return; + } + + return parseDecimal(x, v.toString()); + } + + if (t === 'string') { + if ((i = v.charCodeAt(0)) === 45) { // minus sign + v = v.slice(1); + x.s = -1; + } else { + if (i === 43) v = v.slice(1); // plus sign + x.s = 1; + } + + return isDecimal.test(v) ? parseDecimal(x, v) : parseOther(x, v); + } + + if (t === 'bigint') { + if (v < 0) { + v = -v; + x.s = -1; + } else { + x.s = 1; + } + + return parseDecimal(x, v.toString()); + } + + throw Error(invalidArgument + v); + } + + Decimal.prototype = P; + + Decimal.ROUND_UP = 0; + Decimal.ROUND_DOWN = 1; + Decimal.ROUND_CEIL = 2; + Decimal.ROUND_FLOOR = 3; + Decimal.ROUND_HALF_UP = 4; + Decimal.ROUND_HALF_DOWN = 5; + Decimal.ROUND_HALF_EVEN = 6; + Decimal.ROUND_HALF_CEIL = 7; + Decimal.ROUND_HALF_FLOOR = 8; + Decimal.EUCLID = 9; + + Decimal.config = Decimal.set = config; + Decimal.clone = clone; + Decimal.isDecimal = isDecimalInstance; + + Decimal.abs = abs; + Decimal.acos = acos; + Decimal.acosh = acosh; // ES6 + Decimal.add = add; + Decimal.asin = asin; + Decimal.asinh = asinh; // ES6 + Decimal.atan = atan; + Decimal.atanh = atanh; // ES6 + Decimal.atan2 = atan2; + Decimal.cbrt = cbrt; // ES6 + Decimal.ceil = ceil; + Decimal.clamp = clamp; + Decimal.cos = cos; + Decimal.cosh = cosh; // ES6 + Decimal.div = div; + Decimal.exp = exp; + Decimal.floor = floor; + Decimal.hypot = hypot; // ES6 + Decimal.ln = ln; + Decimal.log = log; + Decimal.log10 = log10; // ES6 + Decimal.log2 = log2; // ES6 + Decimal.max = max; + Decimal.min = min; + Decimal.mod = mod; + Decimal.mul = mul; + Decimal.pow = pow; + Decimal.random = random; + Decimal.round = round; + Decimal.sign = sign; // ES6 + Decimal.sin = sin; + Decimal.sinh = sinh; // ES6 + Decimal.sqrt = sqrt; + Decimal.sub = sub; + Decimal.sum = sum; + Decimal.tan = tan; + Decimal.tanh = tanh; // ES6 + Decimal.trunc = trunc; // ES6 + + if (obj === void 0) obj = {}; + if (obj) { + if (obj.defaults !== true) { + ps = ['precision', 'rounding', 'toExpNeg', 'toExpPos', 'maxE', 'minE', 'modulo', 'crypto']; + for (i = 0; i < ps.length;) if (!obj.hasOwnProperty(p = ps[i++])) obj[p] = this[p]; + } + } + + Decimal.config(obj); + + return Decimal; +} + + +/* + * Return a new Decimal whose value is `x` divided by `y`, rounded to `precision` significant + * digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * y {number|string|bigint|Decimal} + * + */ +function div(x, y) { + return new this(x).div(y); +} + + +/* + * Return a new Decimal whose value is the natural exponential of `x`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} The power to which to raise the base of the natural log. + * + */ +function exp(x) { + return new this(x).exp(); +} + + +/* + * Return a new Decimal whose value is `x` round to an integer using `ROUND_FLOOR`. + * + * x {number|string|bigint|Decimal} + * + */ +function floor(x) { + return finalise(x = new this(x), x.e + 1, 3); +} + + +/* + * Return a new Decimal whose value is the square root of the sum of the squares of the arguments, + * rounded to `precision` significant digits using rounding mode `rounding`. + * + * hypot(a, b, ...) = sqrt(a^2 + b^2 + ...) + * + * arguments {number|string|bigint|Decimal} + * + */ +function hypot() { + var i, n, + t = new this(0); + + external = false; + + for (i = 0; i < arguments.length;) { + n = new this(arguments[i++]); + if (!n.d) { + if (n.s) { + external = true; + return new this(1 / 0); + } + t = n; + } else if (t.d) { + t = t.plus(n.times(n)); + } + } + + external = true; + + return t.sqrt(); +} + + +/* + * Return true if object is a Decimal instance (where Decimal is any Decimal constructor), + * otherwise return false. + * + */ +function isDecimalInstance(obj) { + return obj instanceof Decimal || obj && obj.toStringTag === tag || false; +} + + +/* + * Return a new Decimal whose value is the natural logarithm of `x`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * + */ +function ln(x) { + return new this(x).ln(); +} + + +/* + * Return a new Decimal whose value is the log of `x` to the base `y`, or to base 10 if no base + * is specified, rounded to `precision` significant digits using rounding mode `rounding`. + * + * log[y](x) + * + * x {number|string|bigint|Decimal} The argument of the logarithm. + * y {number|string|bigint|Decimal} The base of the logarithm. + * + */ +function log(x, y) { + return new this(x).log(y); +} + + +/* + * Return a new Decimal whose value is the base 2 logarithm of `x`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * + */ +function log2(x) { + return new this(x).log(2); +} + + +/* + * Return a new Decimal whose value is the base 10 logarithm of `x`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * + */ +function log10(x) { + return new this(x).log(10); +} + + +/* + * Return a new Decimal whose value is the maximum of the arguments. + * + * arguments {number|string|bigint|Decimal} + * + */ +function max() { + return maxOrMin(this, arguments, -1); +} + + +/* + * Return a new Decimal whose value is the minimum of the arguments. + * + * arguments {number|string|bigint|Decimal} + * + */ +function min() { + return maxOrMin(this, arguments, 1); +} + + +/* + * Return a new Decimal whose value is `x` modulo `y`, rounded to `precision` significant digits + * using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * y {number|string|bigint|Decimal} + * + */ +function mod(x, y) { + return new this(x).mod(y); +} + + +/* + * Return a new Decimal whose value is `x` multiplied by `y`, rounded to `precision` significant + * digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * y {number|string|bigint|Decimal} + * + */ +function mul(x, y) { + return new this(x).mul(y); +} + + +/* + * Return a new Decimal whose value is `x` raised to the power `y`, rounded to precision + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} The base. + * y {number|string|bigint|Decimal} The exponent. + * + */ +function pow(x, y) { + return new this(x).pow(y); +} + + +/* + * Returns a new Decimal with a random value equal to or greater than 0 and less than 1, and with + * `sd`, or `Decimal.precision` if `sd` is omitted, significant digits (or less if trailing zeros + * are produced). + * + * [sd] {number} Significant digits. Integer, 0 to MAX_DIGITS inclusive. + * + */ +function random(sd) { + var d, e, k, n, + i = 0, + r = new this(1), + rd = []; + + if (sd === void 0) sd = this.precision; + else checkInt32(sd, 1, MAX_DIGITS); + + k = Math.ceil(sd / LOG_BASE); + + if (!this.crypto) { + for (; i < k;) rd[i++] = Math.random() * 1e7 | 0; + + // Browsers supporting crypto.getRandomValues. + } else if (crypto.getRandomValues) { + d = crypto.getRandomValues(new Uint32Array(k)); + + for (; i < k;) { + n = d[i]; + + // 0 <= n < 4294967296 + // Probability n >= 4.29e9, is 4967296 / 4294967296 = 0.00116 (1 in 865). + if (n >= 4.29e9) { + d[i] = crypto.getRandomValues(new Uint32Array(1))[0]; + } else { + + // 0 <= n <= 4289999999 + // 0 <= (n % 1e7) <= 9999999 + rd[i++] = n % 1e7; + } + } + + // Node.js supporting crypto.randomBytes. + } else if (crypto.randomBytes) { + + // buffer + d = crypto.randomBytes(k *= 4); + + for (; i < k;) { + + // 0 <= n < 2147483648 + n = d[i] + (d[i + 1] << 8) + (d[i + 2] << 16) + ((d[i + 3] & 0x7f) << 24); + + // Probability n >= 2.14e9, is 7483648 / 2147483648 = 0.0035 (1 in 286). + if (n >= 2.14e9) { + crypto.randomBytes(4).copy(d, i); + } else { + + // 0 <= n <= 2139999999 + // 0 <= (n % 1e7) <= 9999999 + rd.push(n % 1e7); + i += 4; + } + } + + i = k / 4; + } else { + throw Error(cryptoUnavailable); + } + + k = rd[--i]; + sd %= LOG_BASE; + + // Convert trailing digits to zeros according to sd. + if (k && sd) { + n = mathpow(10, LOG_BASE - sd); + rd[i] = (k / n | 0) * n; + } + + // Remove trailing words which are zero. + for (; rd[i] === 0; i--) rd.pop(); + + // Zero? + if (i < 0) { + e = 0; + rd = [0]; + } else { + e = -1; + + // Remove leading words which are zero and adjust exponent accordingly. + for (; rd[0] === 0; e -= LOG_BASE) rd.shift(); + + // Count the digits of the first word of rd to determine leading zeros. + for (k = 1, n = rd[0]; n >= 10; n /= 10) k++; + + // Adjust the exponent for leading zeros of the first word of rd. + if (k < LOG_BASE) e -= LOG_BASE - k; + } + + r.e = e; + r.d = rd; + + return r; +} + + +/* + * Return a new Decimal whose value is `x` rounded to an integer using rounding mode `rounding`. + * + * To emulate `Math.round`, set rounding to 7 (ROUND_HALF_CEIL). + * + * x {number|string|bigint|Decimal} + * + */ +function round(x) { + return finalise(x = new this(x), x.e + 1, this.rounding); +} + + +/* + * Return + * 1 if x > 0, + * -1 if x < 0, + * 0 if x is 0, + * -0 if x is -0, + * NaN otherwise + * + * x {number|string|bigint|Decimal} + * + */ +function sign(x) { + x = new this(x); + return x.d ? (x.d[0] ? x.s : 0 * x.s) : x.s || NaN; +} + + +/* + * Return a new Decimal whose value is the sine of `x`, rounded to `precision` significant digits + * using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} A value in radians. + * + */ +function sin(x) { + return new this(x).sin(); +} + + +/* + * Return a new Decimal whose value is the hyperbolic sine of `x`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} A value in radians. + * + */ +function sinh(x) { + return new this(x).sinh(); +} + + +/* + * Return a new Decimal whose value is the square root of `x`, rounded to `precision` significant + * digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * + */ +function sqrt(x) { + return new this(x).sqrt(); +} + + +/* + * Return a new Decimal whose value is `x` minus `y`, rounded to `precision` significant digits + * using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} + * y {number|string|bigint|Decimal} + * + */ +function sub(x, y) { + return new this(x).sub(y); +} + + +/* + * Return a new Decimal whose value is the sum of the arguments, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * Only the result is rounded, not the intermediate calculations. + * + * arguments {number|string|bigint|Decimal} + * + */ +function sum() { + var i = 0, + args = arguments, + x = new this(args[i]); + + external = false; + for (; x.s && ++i < args.length;) x = x.plus(args[i]); + external = true; + + return finalise(x, this.precision, this.rounding); +} + + +/* + * Return a new Decimal whose value is the tangent of `x`, rounded to `precision` significant + * digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} A value in radians. + * + */ +function tan(x) { + return new this(x).tan(); +} + + +/* + * Return a new Decimal whose value is the hyperbolic tangent of `x`, rounded to `precision` + * significant digits using rounding mode `rounding`. + * + * x {number|string|bigint|Decimal} A value in radians. + * + */ +function tanh(x) { + return new this(x).tanh(); +} + + +/* + * Return a new Decimal whose value is `x` truncated to an integer. + * + * x {number|string|bigint|Decimal} + * + */ +function trunc(x) { + return finalise(x = new this(x), x.e + 1, 1); +} + + +P[Symbol.for('nodejs.util.inspect.custom')] = P.toString; +P[Symbol.toStringTag] = 'Decimal'; + +// Create and configure initial Decimal constructor. +export var Decimal = P.constructor = clone(DEFAULTS); + +// Create the internal constants from their string values. +LN10 = new Decimal(LN10); +PI = new Decimal(PI); + +export default Decimal;