| 1 | var baseRandom = require('./_baseRandom'),
|
|---|
| 2 | isIterateeCall = require('./_isIterateeCall'),
|
|---|
| 3 | toFinite = require('./toFinite');
|
|---|
| 4 |
|
|---|
| 5 | /** Built-in method references without a dependency on `root`. */
|
|---|
| 6 | var freeParseFloat = parseFloat;
|
|---|
| 7 |
|
|---|
| 8 | /* Built-in method references for those with the same name as other `lodash` methods. */
|
|---|
| 9 | var nativeMin = Math.min,
|
|---|
| 10 | nativeRandom = Math.random;
|
|---|
| 11 |
|
|---|
| 12 | /**
|
|---|
| 13 | * Produces a random number between the inclusive `lower` and `upper` bounds.
|
|---|
| 14 | * If only one argument is provided a number between `0` and the given number
|
|---|
| 15 | * is returned. If `floating` is `true`, or either `lower` or `upper` are
|
|---|
| 16 | * floats, a floating-point number is returned instead of an integer.
|
|---|
| 17 | *
|
|---|
| 18 | * **Note:** JavaScript follows the IEEE-754 standard for resolving
|
|---|
| 19 | * floating-point values which can produce unexpected results.
|
|---|
| 20 | *
|
|---|
| 21 | * **Note:** If `lower` is greater than `upper`, the values are swapped.
|
|---|
| 22 | *
|
|---|
| 23 | * @static
|
|---|
| 24 | * @memberOf _
|
|---|
| 25 | * @since 0.7.0
|
|---|
| 26 | * @category Number
|
|---|
| 27 | * @param {number} [lower=0] The lower bound.
|
|---|
| 28 | * @param {number} [upper=1] The upper bound.
|
|---|
| 29 | * @param {boolean} [floating] Specify returning a floating-point number.
|
|---|
| 30 | * @returns {number} Returns the random number.
|
|---|
| 31 | * @example
|
|---|
| 32 | *
|
|---|
| 33 | * _.random(0, 5);
|
|---|
| 34 | * // => an integer between 0 and 5
|
|---|
| 35 | *
|
|---|
| 36 | * // when lower is greater than upper the values are swapped
|
|---|
| 37 | * _.random(5, 0);
|
|---|
| 38 | * // => an integer between 0 and 5
|
|---|
| 39 | *
|
|---|
| 40 | * _.random(5);
|
|---|
| 41 | * // => also an integer between 0 and 5
|
|---|
| 42 | *
|
|---|
| 43 | * _.random(-5);
|
|---|
| 44 | * // => an integer between -5 and 0
|
|---|
| 45 | *
|
|---|
| 46 | * _.random(5, true);
|
|---|
| 47 | * // => a floating-point number between 0 and 5
|
|---|
| 48 | *
|
|---|
| 49 | * _.random(1.2, 5.2);
|
|---|
| 50 | * // => a floating-point number between 1.2 and 5.2
|
|---|
| 51 | */
|
|---|
| 52 | function random(lower, upper, floating) {
|
|---|
| 53 | if (floating && typeof floating != 'boolean' && isIterateeCall(lower, upper, floating)) {
|
|---|
| 54 | upper = floating = undefined;
|
|---|
| 55 | }
|
|---|
| 56 | if (floating === undefined) {
|
|---|
| 57 | if (typeof upper == 'boolean') {
|
|---|
| 58 | floating = upper;
|
|---|
| 59 | upper = undefined;
|
|---|
| 60 | }
|
|---|
| 61 | else if (typeof lower == 'boolean') {
|
|---|
| 62 | floating = lower;
|
|---|
| 63 | lower = undefined;
|
|---|
| 64 | }
|
|---|
| 65 | }
|
|---|
| 66 | if (lower === undefined && upper === undefined) {
|
|---|
| 67 | lower = 0;
|
|---|
| 68 | upper = 1;
|
|---|
| 69 | }
|
|---|
| 70 | else {
|
|---|
| 71 | lower = toFinite(lower);
|
|---|
| 72 | if (upper === undefined) {
|
|---|
| 73 | upper = lower;
|
|---|
| 74 | lower = 0;
|
|---|
| 75 | } else {
|
|---|
| 76 | upper = toFinite(upper);
|
|---|
| 77 | }
|
|---|
| 78 | }
|
|---|
| 79 | if (lower > upper) {
|
|---|
| 80 | var temp = lower;
|
|---|
| 81 | lower = upper;
|
|---|
| 82 | upper = temp;
|
|---|
| 83 | }
|
|---|
| 84 | if (floating || lower % 1 || upper % 1) {
|
|---|
| 85 | var rand = nativeRandom();
|
|---|
| 86 | return nativeMin(lower + (rand * (upper - lower + freeParseFloat('1e-' + ((rand + '').length - 1)))), upper);
|
|---|
| 87 | }
|
|---|
| 88 | return baseRandom(lower, upper);
|
|---|
| 89 | }
|
|---|
| 90 |
|
|---|
| 91 | module.exports = random;
|
|---|