1 | "use strict";
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2 | Object.defineProperty(exports, "__esModule", { value: true });
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3 | exports.default = exports.JsHistogram = void 0;
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4 | /*
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5 | * This is a TypeScript port of the original Java version, which was written by
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6 | * Gil Tene as described in
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7 | * https://github.com/HdrHistogram/HdrHistogram
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8 | * and released to the public domain, as explained at
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9 | * http://creativecommons.org/publicdomain/zero/1.0/
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10 | */
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11 | const RecordedValuesIterator_1 = require("./RecordedValuesIterator");
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12 | const PercentileIterator_1 = require("./PercentileIterator");
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13 | const formatters_1 = require("./formatters");
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14 | const ulp_1 = require("./ulp");
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15 | const Histogram_1 = require("./Histogram");
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16 | const { pow, floor, ceil, log2, max, min } = Math;
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17 | class JsHistogram {
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18 | constructor(lowestDiscernibleValue, highestTrackableValue, numberOfSignificantValueDigits) {
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19 | this.autoResize = false;
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20 | this.startTimeStampMsec = Number.MAX_SAFE_INTEGER;
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21 | this.endTimeStampMsec = 0;
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22 | this.tag = Histogram_1.NO_TAG;
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23 | this.maxValue = 0;
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24 | this.minNonZeroValue = Number.MAX_SAFE_INTEGER;
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25 | this.identity = 0;
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26 | this.highestTrackableValue = 0;
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27 | this.lowestDiscernibleValue = 0;
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28 | this.numberOfSignificantValueDigits = 0;
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29 | this.bucketCount = 0;
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30 | this.subBucketCount = 0;
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31 | this.countsArrayLength = 0;
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32 | this.wordSizeInBytes = 0;
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33 | // Verify argument validity
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34 | if (lowestDiscernibleValue < 1) {
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35 | throw new Error("lowestDiscernibleValue must be >= 1");
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36 | }
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37 | if (highestTrackableValue < 2 * lowestDiscernibleValue) {
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38 | throw new Error(`highestTrackableValue must be >= 2 * lowestDiscernibleValue ( 2 * ${lowestDiscernibleValue} )`);
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39 | }
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40 | if (numberOfSignificantValueDigits < 0 ||
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41 | numberOfSignificantValueDigits > 5) {
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42 | throw new Error("numberOfSignificantValueDigits must be between 0 and 5");
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43 | }
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44 | this.identity = JsHistogram.identityBuilder++;
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45 | this.init(lowestDiscernibleValue, highestTrackableValue, numberOfSignificantValueDigits);
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46 | }
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47 | incrementTotalCount() {
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48 | this._totalCount++;
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49 | }
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50 | addToTotalCount(value) {
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51 | this._totalCount += value;
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52 | }
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53 | setTotalCount(value) {
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54 | this._totalCount = value;
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55 | }
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56 | /**
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57 | * Get the total count of all recorded values in the histogram
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58 | * @return the total count of all recorded values in the histogram
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59 | */
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60 | get totalCount() {
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61 | return this._totalCount;
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62 | }
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63 | updatedMaxValue(value) {
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64 | const internalValue = value + this.unitMagnitudeMask;
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65 | this.maxValue = internalValue;
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66 | }
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67 | updateMinNonZeroValue(value) {
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68 | if (value <= this.unitMagnitudeMask) {
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69 | return;
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70 | }
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71 | const internalValue = floor(value / this.lowestDiscernibleValueRounded) *
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72 | this.lowestDiscernibleValueRounded;
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73 | this.minNonZeroValue = internalValue;
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74 | }
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75 | init(lowestDiscernibleValue, highestTrackableValue, numberOfSignificantValueDigits) {
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76 | this.lowestDiscernibleValue = lowestDiscernibleValue;
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77 | this.highestTrackableValue = highestTrackableValue;
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78 | this.numberOfSignificantValueDigits = numberOfSignificantValueDigits;
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79 | /*
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80 | * Given a 3 decimal point accuracy, the expectation is obviously for "+/- 1 unit at 1000". It also means that
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81 | * it's "ok to be +/- 2 units at 2000". The "tricky" thing is that it is NOT ok to be +/- 2 units at 1999. Only
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82 | * starting at 2000. So internally, we need to maintain single unit resolution to 2x 10^decimalPoints.
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83 | */
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84 | const largestValueWithSingleUnitResolution = 2 * floor(pow(10, numberOfSignificantValueDigits));
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85 | this.unitMagnitude = floor(log2(lowestDiscernibleValue));
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86 | this.lowestDiscernibleValueRounded = pow(2, this.unitMagnitude);
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87 | this.unitMagnitudeMask = this.lowestDiscernibleValueRounded - 1;
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88 | // We need to maintain power-of-two subBucketCount (for clean direct indexing) that is large enough to
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89 | // provide unit resolution to at least largestValueWithSingleUnitResolution. So figure out
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90 | // largestValueWithSingleUnitResolution's nearest power-of-two (rounded up), and use that:
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91 | const subBucketCountMagnitude = ceil(log2(largestValueWithSingleUnitResolution));
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92 | this.subBucketHalfCountMagnitude =
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93 | (subBucketCountMagnitude > 1 ? subBucketCountMagnitude : 1) - 1;
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94 | this.subBucketCount = pow(2, this.subBucketHalfCountMagnitude + 1);
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95 | this.subBucketHalfCount = this.subBucketCount / 2;
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96 | this.subBucketMask =
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97 | (floor(this.subBucketCount) - 1) * pow(2, this.unitMagnitude);
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98 | this.establishSize(highestTrackableValue);
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99 | this.leadingZeroCountBase =
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100 | 53 - this.unitMagnitude - this.subBucketHalfCountMagnitude - 1;
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101 | this.percentileIterator = new PercentileIterator_1.default(this, 1);
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102 | this.recordedValuesIterator = new RecordedValuesIterator_1.default(this);
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103 | }
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104 | /**
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105 | * The buckets (each of which has subBucketCount sub-buckets, here assumed to be 2048 as an example) overlap:
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106 | *
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107 | * <pre>
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108 | * The 0'th bucket covers from 0...2047 in multiples of 1, using all 2048 sub-buckets
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109 | * The 1'th bucket covers from 2048..4097 in multiples of 2, using only the top 1024 sub-buckets
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110 | * The 2'th bucket covers from 4096..8191 in multiple of 4, using only the top 1024 sub-buckets
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111 | * ...
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112 | * </pre>
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113 | *
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114 | * Bucket 0 is "special" here. It is the only one that has 2048 entries. All the rest have 1024 entries (because
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115 | * their bottom half overlaps with and is already covered by the all of the previous buckets put together). In other
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116 | * words, the k'th bucket could represent 0 * 2^k to 2048 * 2^k in 2048 buckets with 2^k precision, but the midpoint
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117 | * of 1024 * 2^k = 2048 * 2^(k-1) = the k-1'th bucket's end, so we would use the previous bucket for those lower
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118 | * values as it has better precision.
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119 | */
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120 | establishSize(newHighestTrackableValue) {
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121 | // establish counts array length:
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122 | this.countsArrayLength = this.determineArrayLengthNeeded(newHighestTrackableValue);
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123 | // establish exponent range needed to support the trackable value with no overflow:
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124 | this.bucketCount = this.getBucketsNeededToCoverValue(newHighestTrackableValue);
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125 | // establish the new highest trackable value:
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126 | this.highestTrackableValue = newHighestTrackableValue;
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127 | }
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128 | determineArrayLengthNeeded(highestTrackableValue) {
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129 | if (highestTrackableValue < 2 * this.lowestDiscernibleValue) {
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130 | throw new Error("highestTrackableValue (" +
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131 | highestTrackableValue +
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132 | ") cannot be < (2 * lowestDiscernibleValue)");
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133 | }
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134 | //determine counts array length needed:
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135 | const countsArrayLength = this.getLengthForNumberOfBuckets(this.getBucketsNeededToCoverValue(highestTrackableValue));
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136 | return countsArrayLength;
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137 | }
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138 | /**
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139 | * If we have N such that subBucketCount * 2^N > max value, we need storage for N+1 buckets, each with enough
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140 | * slots to hold the top half of the subBucketCount (the lower half is covered by previous buckets), and the +1
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141 | * being used for the lower half of the 0'th bucket. Or, equivalently, we need 1 more bucket to capture the max
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142 | * value if we consider the sub-bucket length to be halved.
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143 | */
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144 | getLengthForNumberOfBuckets(numberOfBuckets) {
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145 | const lengthNeeded = (numberOfBuckets + 1) * (this.subBucketCount / 2);
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146 | return lengthNeeded;
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147 | }
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148 | getBucketsNeededToCoverValue(value) {
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149 | // the k'th bucket can express from 0 * 2^k to subBucketCount * 2^k in units of 2^k
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150 | let smallestUntrackableValue = this.subBucketCount * pow(2, this.unitMagnitude);
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151 | // always have at least 1 bucket
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152 | let bucketsNeeded = 1;
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153 | while (smallestUntrackableValue <= value) {
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154 | if (smallestUntrackableValue > Number.MAX_SAFE_INTEGER / 2) {
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155 | // TODO check array max size in JavaScript
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156 | // next shift will overflow, meaning that bucket could represent values up to ones greater than
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157 | // Number.MAX_SAFE_INTEGER, so it's the last bucket
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158 | return bucketsNeeded + 1;
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159 | }
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160 | smallestUntrackableValue = smallestUntrackableValue * 2;
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161 | bucketsNeeded++;
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162 | }
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163 | return bucketsNeeded;
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164 | }
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165 | /**
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166 | * Record a value in the histogram
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167 | *
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168 | * @param value The value to be recorded
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169 | * @throws may throw Error if value is exceeds highestTrackableValue
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170 | */
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171 | recordValue(value) {
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172 | this.recordSingleValue(value);
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173 | }
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174 | recordSingleValue(value) {
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175 | const countsIndex = this.countsArrayIndex(value);
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176 | if (countsIndex >= this.countsArrayLength) {
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177 | this.handleRecordException(1, value);
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178 | }
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179 | else {
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180 | this.incrementCountAtIndex(countsIndex);
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181 | }
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182 | this.updateMinAndMax(value);
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183 | this.incrementTotalCount();
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184 | }
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185 | handleRecordException(count, value) {
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186 | if (!this.autoResize) {
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187 | throw new Error("Value " + value + " is outside of histogram covered range");
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188 | }
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189 | this.resize(value);
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190 | var countsIndex = this.countsArrayIndex(value);
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191 | this.addToCountAtIndex(countsIndex, count);
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192 | this.highestTrackableValue = this.highestEquivalentValue(this.valueFromIndex(this.countsArrayLength - 1));
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193 | }
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194 | countsArrayIndex(value) {
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195 | if (value < 0) {
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196 | throw new Error("Histogram recorded value cannot be negative.");
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197 | }
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198 | const bucketIndex = this.getBucketIndex(value);
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199 | const subBucketIndex = this.getSubBucketIndex(value, bucketIndex);
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200 | return this.computeCountsArrayIndex(bucketIndex, subBucketIndex);
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201 | }
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202 | computeCountsArrayIndex(bucketIndex, subBucketIndex) {
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203 | // TODO
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204 | //assert(subBucketIndex < subBucketCount);
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205 | //assert(bucketIndex == 0 || (subBucketIndex >= subBucketHalfCount));
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206 | // Calculate the index for the first entry that will be used in the bucket (halfway through subBucketCount).
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207 | // For bucketIndex 0, all subBucketCount entries may be used, but bucketBaseIndex is still set in the middle.
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208 | const bucketBaseIndex = (bucketIndex + 1) * pow(2, this.subBucketHalfCountMagnitude);
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209 | // Calculate the offset in the bucket. This subtraction will result in a positive value in all buckets except
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210 | // the 0th bucket (since a value in that bucket may be less than half the bucket's 0 to subBucketCount range).
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211 | // However, this works out since we give bucket 0 twice as much space.
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212 | const offsetInBucket = subBucketIndex - this.subBucketHalfCount;
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213 | // The following is the equivalent of ((subBucketIndex - subBucketHalfCount) + bucketBaseIndex;
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214 | return bucketBaseIndex + offsetInBucket;
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215 | }
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216 | /**
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217 | * @return the lowest (and therefore highest precision) bucket index that can represent the value
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218 | */
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219 | getBucketIndex(value) {
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220 | // Calculates the number of powers of two by which the value is greater than the biggest value that fits in
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221 | // bucket 0. This is the bucket index since each successive bucket can hold a value 2x greater.
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222 | // The mask maps small values to bucket 0.
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223 | // return this.leadingZeroCountBase - Long.numberOfLeadingZeros(value | subBucketMask);
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224 | return max(floor(log2(value)) -
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225 | this.subBucketHalfCountMagnitude -
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226 | this.unitMagnitude, 0);
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227 | }
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228 | getSubBucketIndex(value, bucketIndex) {
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229 | // For bucketIndex 0, this is just value, so it may be anywhere in 0 to subBucketCount.
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230 | // For other bucketIndex, this will always end up in the top half of subBucketCount: assume that for some bucket
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231 | // k > 0, this calculation will yield a value in the bottom half of 0 to subBucketCount. Then, because of how
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232 | // buckets overlap, it would have also been in the top half of bucket k-1, and therefore would have
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233 | // returned k-1 in getBucketIndex(). Since we would then shift it one fewer bits here, it would be twice as big,
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234 | // and therefore in the top half of subBucketCount.
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235 | return floor(value / pow(2, bucketIndex + this.unitMagnitude));
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236 | }
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237 | updateMinAndMax(value) {
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238 | if (value > this.maxValue) {
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239 | this.updatedMaxValue(value);
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240 | }
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241 | if (value < this.minNonZeroValue && value !== 0) {
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242 | this.updateMinNonZeroValue(value);
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243 | }
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244 | }
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245 | /**
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246 | * Get the value at a given percentile.
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247 | * When the given percentile is > 0.0, the value returned is the value that the given
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248 | * percentage of the overall recorded value entries in the histogram are either smaller than
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249 | * or equivalent to. When the given percentile is 0.0, the value returned is the value that all value
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250 | * entries in the histogram are either larger than or equivalent to.
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251 | * <p>
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252 | * Note that two values are "equivalent" in this statement if
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253 | * {@link org.HdrHistogram.JsHistogram#valuesAreEquivalent} would return true.
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254 | *
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255 | * @param percentile The percentile for which to return the associated value
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256 | * @return The value that the given percentage of the overall recorded value entries in the
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257 | * histogram are either smaller than or equivalent to. When the percentile is 0.0, returns the
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258 | * value that all value entries in the histogram are either larger than or equivalent to.
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259 | */
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260 | getValueAtPercentile(percentile) {
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261 | const requestedPercentile = min(percentile, 100); // Truncate down to 100%
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262 | // round count up to nearest integer, to ensure that the largest value that the requested percentile
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263 | // of overall recorded values is actually included. However, this must be done with care:
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264 | //
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265 | // First, Compute fp value for count at the requested percentile. Note that fp result end up
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266 | // being 1 ulp larger than the correct integer count for this percentile:
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267 | const fpCountAtPercentile = (requestedPercentile / 100.0) * this.totalCount;
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268 | // Next, round up, but make sure to prevent <= 1 ulp inaccurancies in the above fp math from
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269 | // making us skip a count:
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270 | const countAtPercentile = max(ceil(fpCountAtPercentile - ulp_1.default(fpCountAtPercentile)), // round up
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271 | 1 // Make sure we at least reach the first recorded entry
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272 | );
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273 | let totalToCurrentIndex = 0;
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274 | for (let i = 0; i < this.countsArrayLength; i++) {
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275 | totalToCurrentIndex += this.getCountAtIndex(i);
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276 | if (totalToCurrentIndex >= countAtPercentile) {
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277 | var valueAtIndex = this.valueFromIndex(i);
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278 | return percentile === 0.0
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279 | ? this.lowestEquivalentValue(valueAtIndex)
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280 | : this.highestEquivalentValue(valueAtIndex);
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281 | }
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282 | }
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283 | return 0;
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284 | }
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285 | valueFromIndexes(bucketIndex, subBucketIndex) {
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286 | return subBucketIndex * pow(2, bucketIndex + this.unitMagnitude);
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287 | }
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288 | valueFromIndex(index) {
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289 | let bucketIndex = floor(index / this.subBucketHalfCount) - 1;
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290 | let subBucketIndex = (index % this.subBucketHalfCount) + this.subBucketHalfCount;
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291 | if (bucketIndex < 0) {
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292 | subBucketIndex -= this.subBucketHalfCount;
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293 | bucketIndex = 0;
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294 | }
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295 | return this.valueFromIndexes(bucketIndex, subBucketIndex);
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296 | }
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297 | /**
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298 | * Get the lowest value that is equivalent to the given value within the histogram's resolution.
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299 | * Where "equivalent" means that value samples recorded for any two
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300 | * equivalent values are counted in a common total count.
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301 | *
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302 | * @param value The given value
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303 | * @return The lowest value that is equivalent to the given value within the histogram's resolution.
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304 | */
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305 | lowestEquivalentValue(value) {
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306 | const bucketIndex = this.getBucketIndex(value);
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307 | const subBucketIndex = this.getSubBucketIndex(value, bucketIndex);
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308 | const thisValueBaseLevel = this.valueFromIndexes(bucketIndex, subBucketIndex);
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309 | return thisValueBaseLevel;
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310 | }
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311 | /**
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312 | * Get the highest value that is equivalent to the given value within the histogram's resolution.
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313 | * Where "equivalent" means that value samples recorded for any two
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314 | * equivalent values are counted in a common total count.
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315 | *
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316 | * @param value The given value
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317 | * @return The highest value that is equivalent to the given value within the histogram's resolution.
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318 | */
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319 | highestEquivalentValue(value) {
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320 | return this.nextNonEquivalentValue(value) - 1;
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321 | }
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322 | /**
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323 | * Get the next value that is not equivalent to the given value within the histogram's resolution.
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324 | * Where "equivalent" means that value samples recorded for any two
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325 | * equivalent values are counted in a common total count.
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326 | *
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327 | * @param value The given value
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328 | * @return The next value that is not equivalent to the given value within the histogram's resolution.
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329 | */
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330 | nextNonEquivalentValue(value) {
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331 | return (this.lowestEquivalentValue(value) + this.sizeOfEquivalentValueRange(value));
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332 | }
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333 | /**
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334 | * Get the size (in value units) of the range of values that are equivalent to the given value within the
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335 | * histogram's resolution. Where "equivalent" means that value samples recorded for any two
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336 | * equivalent values are counted in a common total count.
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337 | *
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338 | * @param value The given value
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339 | * @return The size of the range of values equivalent to the given value.
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340 | */
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341 | sizeOfEquivalentValueRange(value) {
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342 | const bucketIndex = this.getBucketIndex(value);
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343 | const subBucketIndex = this.getSubBucketIndex(value, bucketIndex);
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344 | const distanceToNextValue = pow(2, this.unitMagnitude +
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345 | (subBucketIndex >= this.subBucketCount ? bucketIndex + 1 : bucketIndex));
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346 | return distanceToNextValue;
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347 | }
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348 | /**
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349 | * Get a value that lies in the middle (rounded up) of the range of values equivalent the given value.
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350 | * Where "equivalent" means that value samples recorded for any two
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351 | * equivalent values are counted in a common total count.
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352 | *
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353 | * @param value The given value
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354 | * @return The value lies in the middle (rounded up) of the range of values equivalent the given value.
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355 | */
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356 | medianEquivalentValue(value) {
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357 | return (this.lowestEquivalentValue(value) +
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358 | floor(this.sizeOfEquivalentValueRange(value) / 2));
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359 | }
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360 | /**
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361 | * Get the computed mean value of all recorded values in the histogram
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362 | *
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363 | * @return the mean value (in value units) of the histogram data
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364 | */
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365 | get mean() {
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366 | if (this.totalCount === 0) {
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367 | return 0;
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368 | }
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369 | this.recordedValuesIterator.reset();
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370 | let totalValue = 0;
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371 | while (this.recordedValuesIterator.hasNext()) {
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372 | const iterationValue = this.recordedValuesIterator.next();
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373 | totalValue +=
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374 | this.medianEquivalentValue(iterationValue.valueIteratedTo) *
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375 | iterationValue.countAtValueIteratedTo;
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376 | }
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377 | return totalValue / this.totalCount;
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378 | }
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379 | getStdDeviation(mean = this.mean) {
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380 | if (this.totalCount === 0) {
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381 | return 0;
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382 | }
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383 | let geometric_deviation_total = 0.0;
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384 | this.recordedValuesIterator.reset();
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385 | while (this.recordedValuesIterator.hasNext()) {
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386 | const iterationValue = this.recordedValuesIterator.next();
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387 | const deviation = this.medianEquivalentValue(iterationValue.valueIteratedTo) - mean;
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388 | geometric_deviation_total +=
|
---|
389 | deviation * deviation * iterationValue.countAddedInThisIterationStep;
|
---|
390 | }
|
---|
391 | const std_deviation = Math.sqrt(geometric_deviation_total / this.totalCount);
|
---|
392 | return std_deviation;
|
---|
393 | }
|
---|
394 | /**
|
---|
395 | * Get the computed standard deviation of all recorded values in the histogram
|
---|
396 | *
|
---|
397 | * @return the standard deviation (in value units) of the histogram data
|
---|
398 | */
|
---|
399 | get stdDeviation() {
|
---|
400 | if (this.totalCount === 0) {
|
---|
401 | return 0;
|
---|
402 | }
|
---|
403 | const mean = this.mean;
|
---|
404 | let geometric_deviation_total = 0.0;
|
---|
405 | this.recordedValuesIterator.reset();
|
---|
406 | while (this.recordedValuesIterator.hasNext()) {
|
---|
407 | const iterationValue = this.recordedValuesIterator.next();
|
---|
408 | const deviation = this.medianEquivalentValue(iterationValue.valueIteratedTo) - mean;
|
---|
409 | geometric_deviation_total +=
|
---|
410 | deviation * deviation * iterationValue.countAddedInThisIterationStep;
|
---|
411 | }
|
---|
412 | const std_deviation = Math.sqrt(geometric_deviation_total / this.totalCount);
|
---|
413 | return std_deviation;
|
---|
414 | }
|
---|
415 | /**
|
---|
416 | * Produce textual representation of the value distribution of histogram data by percentile. The distribution is
|
---|
417 | * output with exponentially increasing resolution, with each exponentially decreasing half-distance containing
|
---|
418 | * <i>dumpTicksPerHalf</i> percentile reporting tick points.
|
---|
419 | *
|
---|
420 | * @param printStream Stream into which the distribution will be output
|
---|
421 | * <p>
|
---|
422 | * @param percentileTicksPerHalfDistance The number of reporting points per exponentially decreasing half-distance
|
---|
423 | * <p>
|
---|
424 | * @param outputValueUnitScalingRatio The scaling factor by which to divide histogram recorded values units in
|
---|
425 | * output
|
---|
426 | * @param useCsvFormat Output in CSV format if true. Otherwise use plain text form.
|
---|
427 | */
|
---|
428 | outputPercentileDistribution(percentileTicksPerHalfDistance = 5, outputValueUnitScalingRatio = 1, useCsvFormat = false) {
|
---|
429 | let result = "";
|
---|
430 | if (useCsvFormat) {
|
---|
431 | result += '"Value","Percentile","TotalCount","1/(1-Percentile)"\n';
|
---|
432 | }
|
---|
433 | else {
|
---|
434 | result += " Value Percentile TotalCount 1/(1-Percentile)\n\n";
|
---|
435 | }
|
---|
436 | const iterator = this.percentileIterator;
|
---|
437 | iterator.reset(percentileTicksPerHalfDistance);
|
---|
438 | let lineFormatter;
|
---|
439 | let lastLineFormatter;
|
---|
440 | if (useCsvFormat) {
|
---|
441 | const valueFormatter = formatters_1.floatFormatter(0, this.numberOfSignificantValueDigits);
|
---|
442 | const percentileFormatter = formatters_1.floatFormatter(0, 12);
|
---|
443 | const lastFormatter = formatters_1.floatFormatter(0, 2);
|
---|
444 | lineFormatter = (iterationValue) => valueFormatter(iterationValue.valueIteratedTo / outputValueUnitScalingRatio) +
|
---|
445 | "," +
|
---|
446 | percentileFormatter(iterationValue.percentileLevelIteratedTo / 100) +
|
---|
447 | "," +
|
---|
448 | iterationValue.totalCountToThisValue +
|
---|
449 | "," +
|
---|
450 | lastFormatter(1 / (1 - iterationValue.percentileLevelIteratedTo / 100)) +
|
---|
451 | "\n";
|
---|
452 | lastLineFormatter = (iterationValue) => valueFormatter(iterationValue.valueIteratedTo / outputValueUnitScalingRatio) +
|
---|
453 | "," +
|
---|
454 | percentileFormatter(iterationValue.percentileLevelIteratedTo / 100) +
|
---|
455 | "," +
|
---|
456 | iterationValue.totalCountToThisValue +
|
---|
457 | ",Infinity\n";
|
---|
458 | }
|
---|
459 | else {
|
---|
460 | const valueFormatter = formatters_1.floatFormatter(12, this.numberOfSignificantValueDigits);
|
---|
461 | const percentileFormatter = formatters_1.floatFormatter(2, 12);
|
---|
462 | const totalCountFormatter = formatters_1.integerFormatter(10);
|
---|
463 | const lastFormatter = formatters_1.floatFormatter(14, 2);
|
---|
464 | lineFormatter = (iterationValue) => valueFormatter(iterationValue.valueIteratedTo / outputValueUnitScalingRatio) +
|
---|
465 | " " +
|
---|
466 | percentileFormatter(iterationValue.percentileLevelIteratedTo / 100) +
|
---|
467 | " " +
|
---|
468 | totalCountFormatter(iterationValue.totalCountToThisValue) +
|
---|
469 | " " +
|
---|
470 | lastFormatter(1 / (1 - iterationValue.percentileLevelIteratedTo / 100)) +
|
---|
471 | "\n";
|
---|
472 | lastLineFormatter = (iterationValue) => valueFormatter(iterationValue.valueIteratedTo / outputValueUnitScalingRatio) +
|
---|
473 | " " +
|
---|
474 | percentileFormatter(iterationValue.percentileLevelIteratedTo / 100) +
|
---|
475 | " " +
|
---|
476 | totalCountFormatter(iterationValue.totalCountToThisValue) +
|
---|
477 | "\n";
|
---|
478 | }
|
---|
479 | while (iterator.hasNext()) {
|
---|
480 | const iterationValue = iterator.next();
|
---|
481 | if (iterationValue.percentileLevelIteratedTo < 100) {
|
---|
482 | result += lineFormatter(iterationValue);
|
---|
483 | }
|
---|
484 | else {
|
---|
485 | result += lastLineFormatter(iterationValue);
|
---|
486 | }
|
---|
487 | }
|
---|
488 | if (!useCsvFormat) {
|
---|
489 | // Calculate and output mean and std. deviation.
|
---|
490 | // Note: mean/std. deviation numbers are very often completely irrelevant when
|
---|
491 | // data is extremely non-normal in distribution (e.g. in cases of strong multi-modal
|
---|
492 | // response time distribution associated with GC pauses). However, reporting these numbers
|
---|
493 | // can be very useful for contrasting with the detailed percentile distribution
|
---|
494 | // reported by outputPercentileDistribution(). It is not at all surprising to find
|
---|
495 | // percentile distributions where results fall many tens or even hundreds of standard
|
---|
496 | // deviations away from the mean - such results simply indicate that the data sampled
|
---|
497 | // exhibits a very non-normal distribution, highlighting situations for which the std.
|
---|
498 | // deviation metric is a useless indicator.
|
---|
499 | //
|
---|
500 | const formatter = formatters_1.floatFormatter(12, this.numberOfSignificantValueDigits);
|
---|
501 | const _mean = this.mean;
|
---|
502 | const mean = formatter(_mean / outputValueUnitScalingRatio);
|
---|
503 | const std_deviation = formatter(this.getStdDeviation(_mean) / outputValueUnitScalingRatio);
|
---|
504 | const max = formatter(this.maxValue / outputValueUnitScalingRatio);
|
---|
505 | const intFormatter = formatters_1.integerFormatter(12);
|
---|
506 | const totalCount = intFormatter(this.totalCount);
|
---|
507 | const bucketCount = intFormatter(this.bucketCount);
|
---|
508 | const subBucketCount = intFormatter(this.subBucketCount);
|
---|
509 | result += `#[Mean = ${mean}, StdDeviation = ${std_deviation}]
|
---|
510 | #[Max = ${max}, Total count = ${totalCount}]
|
---|
511 | #[Buckets = ${bucketCount}, SubBuckets = ${subBucketCount}]
|
---|
512 | `;
|
---|
513 | }
|
---|
514 | return result;
|
---|
515 | }
|
---|
516 | get summary() {
|
---|
517 | return Histogram_1.toSummary(this);
|
---|
518 | }
|
---|
519 | toJSON() {
|
---|
520 | return this.summary;
|
---|
521 | }
|
---|
522 | inspect() {
|
---|
523 | return this.toString();
|
---|
524 | }
|
---|
525 | [Symbol.for("nodejs.util.inspect.custom")]() {
|
---|
526 | return this.toString();
|
---|
527 | }
|
---|
528 | /**
|
---|
529 | * Provide a (conservatively high) estimate of the Histogram's total footprint in bytes
|
---|
530 | *
|
---|
531 | * @return a (conservatively high) estimate of the Histogram's total footprint in bytes
|
---|
532 | */
|
---|
533 | get estimatedFootprintInBytes() {
|
---|
534 | return this._getEstimatedFootprintInBytes();
|
---|
535 | }
|
---|
536 | recordSingleValueWithExpectedInterval(value, expectedIntervalBetweenValueSamples) {
|
---|
537 | this.recordSingleValue(value);
|
---|
538 | if (expectedIntervalBetweenValueSamples <= 0) {
|
---|
539 | return;
|
---|
540 | }
|
---|
541 | for (let missingValue = value - expectedIntervalBetweenValueSamples; missingValue >= expectedIntervalBetweenValueSamples; missingValue -= expectedIntervalBetweenValueSamples) {
|
---|
542 | this.recordSingleValue(missingValue);
|
---|
543 | }
|
---|
544 | }
|
---|
545 | recordCountAtValue(count, value) {
|
---|
546 | const countsIndex = this.countsArrayIndex(value);
|
---|
547 | if (countsIndex >= this.countsArrayLength) {
|
---|
548 | this.handleRecordException(count, value);
|
---|
549 | }
|
---|
550 | else {
|
---|
551 | this.addToCountAtIndex(countsIndex, count);
|
---|
552 | }
|
---|
553 | this.updateMinAndMax(value);
|
---|
554 | this.addToTotalCount(count);
|
---|
555 | }
|
---|
556 | /**
|
---|
557 | * Record a value in the histogram (adding to the value's current count)
|
---|
558 | *
|
---|
559 | * @param value The value to be recorded
|
---|
560 | * @param count The number of occurrences of this value to record
|
---|
561 | * @throws ArrayIndexOutOfBoundsException (may throw) if value is exceeds highestTrackableValue
|
---|
562 | */
|
---|
563 | recordValueWithCount(value, count) {
|
---|
564 | this.recordCountAtValue(count, value);
|
---|
565 | }
|
---|
566 | /**
|
---|
567 | * Record a value in the histogram.
|
---|
568 | * <p>
|
---|
569 | * To compensate for the loss of sampled values when a recorded value is larger than the expected
|
---|
570 | * interval between value samples, Histogram will auto-generate an additional series of decreasingly-smaller
|
---|
571 | * (down to the expectedIntervalBetweenValueSamples) value records.
|
---|
572 | * <p>
|
---|
573 | * Note: This is a at-recording correction method, as opposed to the post-recording correction method provided
|
---|
574 | * by {@link #copyCorrectedForCoordinatedOmission(long)}.
|
---|
575 | * The two methods are mutually exclusive, and only one of the two should be be used on a given data set to correct
|
---|
576 | * for the same coordinated omission issue.
|
---|
577 | * <p>
|
---|
578 | * See notes in the description of the Histogram calls for an illustration of why this corrective behavior is
|
---|
579 | * important.
|
---|
580 | *
|
---|
581 | * @param value The value to record
|
---|
582 | * @param expectedIntervalBetweenValueSamples If expectedIntervalBetweenValueSamples is larger than 0, add
|
---|
583 | * auto-generated value records as appropriate if value is larger
|
---|
584 | * than expectedIntervalBetweenValueSamples
|
---|
585 | * @throws ArrayIndexOutOfBoundsException (may throw) if value is exceeds highestTrackableValue
|
---|
586 | */
|
---|
587 | recordValueWithExpectedInterval(value, expectedIntervalBetweenValueSamples) {
|
---|
588 | this.recordSingleValueWithExpectedInterval(value, expectedIntervalBetweenValueSamples);
|
---|
589 | }
|
---|
590 | recordValueWithCountAndExpectedInterval(value, count, expectedIntervalBetweenValueSamples) {
|
---|
591 | this.recordCountAtValue(count, value);
|
---|
592 | if (expectedIntervalBetweenValueSamples <= 0) {
|
---|
593 | return;
|
---|
594 | }
|
---|
595 | for (let missingValue = value - expectedIntervalBetweenValueSamples; missingValue >= expectedIntervalBetweenValueSamples; missingValue -= expectedIntervalBetweenValueSamples) {
|
---|
596 | this.recordCountAtValue(count, missingValue);
|
---|
597 | }
|
---|
598 | }
|
---|
599 | /**
|
---|
600 | * Add the contents of another histogram to this one, while correcting the incoming data for coordinated omission.
|
---|
601 | * <p>
|
---|
602 | * To compensate for the loss of sampled values when a recorded value is larger than the expected
|
---|
603 | * interval between value samples, the values added will include an auto-generated additional series of
|
---|
604 | * decreasingly-smaller (down to the expectedIntervalBetweenValueSamples) value records for each count found
|
---|
605 | * in the current histogram that is larger than the expectedIntervalBetweenValueSamples.
|
---|
606 | *
|
---|
607 | * Note: This is a post-recording correction method, as opposed to the at-recording correction method provided
|
---|
608 | * by {@link #recordValueWithExpectedInterval(long, long) recordValueWithExpectedInterval}. The two
|
---|
609 | * methods are mutually exclusive, and only one of the two should be be used on a given data set to correct
|
---|
610 | * for the same coordinated omission issue.
|
---|
611 | * by
|
---|
612 | * <p>
|
---|
613 | * See notes in the description of the Histogram calls for an illustration of why this corrective behavior is
|
---|
614 | * important.
|
---|
615 | *
|
---|
616 | * @param otherHistogram The other histogram. highestTrackableValue and largestValueWithSingleUnitResolution must match.
|
---|
617 | * @param expectedIntervalBetweenValueSamples If expectedIntervalBetweenValueSamples is larger than 0, add
|
---|
618 | * auto-generated value records as appropriate if value is larger
|
---|
619 | * than expectedIntervalBetweenValueSamples
|
---|
620 | * @throws ArrayIndexOutOfBoundsException (may throw) if values exceed highestTrackableValue
|
---|
621 | */
|
---|
622 | addWhileCorrectingForCoordinatedOmission(otherHistogram, expectedIntervalBetweenValueSamples) {
|
---|
623 | const toHistogram = this;
|
---|
624 | const otherValues = new RecordedValuesIterator_1.default(otherHistogram);
|
---|
625 | while (otherValues.hasNext()) {
|
---|
626 | const v = otherValues.next();
|
---|
627 | toHistogram.recordValueWithCountAndExpectedInterval(v.valueIteratedTo, v.countAtValueIteratedTo, expectedIntervalBetweenValueSamples);
|
---|
628 | }
|
---|
629 | }
|
---|
630 | /**
|
---|
631 | * Add the contents of another histogram to this one.
|
---|
632 | * <p>
|
---|
633 | * As part of adding the contents, the start/end timestamp range of this histogram will be
|
---|
634 | * extended to include the start/end timestamp range of the other histogram.
|
---|
635 | *
|
---|
636 | * @param otherHistogram The other histogram.
|
---|
637 | * @throws (may throw) if values in fromHistogram's are
|
---|
638 | * higher than highestTrackableValue.
|
---|
639 | */
|
---|
640 | add(otherHistogram) {
|
---|
641 | if (!(otherHistogram instanceof JsHistogram)) {
|
---|
642 | // should be impossible to be in this situation but actually
|
---|
643 | // TypeScript has some flaws...
|
---|
644 | throw new Error("Cannot add a WASM histogram to a regular JS histogram");
|
---|
645 | }
|
---|
646 | const highestRecordableValue = this.highestEquivalentValue(this.valueFromIndex(this.countsArrayLength - 1));
|
---|
647 | if (highestRecordableValue < otherHistogram.maxValue) {
|
---|
648 | if (!this.autoResize) {
|
---|
649 | throw new Error("The other histogram includes values that do not fit in this histogram's range.");
|
---|
650 | }
|
---|
651 | this.resize(otherHistogram.maxValue);
|
---|
652 | }
|
---|
653 | if (this.bucketCount === otherHistogram.bucketCount &&
|
---|
654 | this.subBucketCount === otherHistogram.subBucketCount &&
|
---|
655 | this.unitMagnitude === otherHistogram.unitMagnitude) {
|
---|
656 | // Counts arrays are of the same length and meaning, so we can just iterate and add directly:
|
---|
657 | let observedOtherTotalCount = 0;
|
---|
658 | for (let i = 0; i < otherHistogram.countsArrayLength; i++) {
|
---|
659 | const otherCount = otherHistogram.getCountAtIndex(i);
|
---|
660 | if (otherCount > 0) {
|
---|
661 | this.addToCountAtIndex(i, otherCount);
|
---|
662 | observedOtherTotalCount += otherCount;
|
---|
663 | }
|
---|
664 | }
|
---|
665 | this.setTotalCount(this.totalCount + observedOtherTotalCount);
|
---|
666 | this.updatedMaxValue(max(this.maxValue, otherHistogram.maxValue));
|
---|
667 | this.updateMinNonZeroValue(min(this.minNonZeroValue, otherHistogram.minNonZeroValue));
|
---|
668 | }
|
---|
669 | else {
|
---|
670 | // Arrays are not a direct match (or the other could change on the fly in some valid way),
|
---|
671 | // so we can't just stream through and add them. Instead, go through the array and add each
|
---|
672 | // non-zero value found at it's proper value:
|
---|
673 | // Do max value first, to avoid max value updates on each iteration:
|
---|
674 | const otherMaxIndex = otherHistogram.countsArrayIndex(otherHistogram.maxValue);
|
---|
675 | let otherCount = otherHistogram.getCountAtIndex(otherMaxIndex);
|
---|
676 | this.recordCountAtValue(otherCount, otherHistogram.valueFromIndex(otherMaxIndex));
|
---|
677 | // Record the remaining values, up to but not including the max value:
|
---|
678 | for (let i = 0; i < otherMaxIndex; i++) {
|
---|
679 | otherCount = otherHistogram.getCountAtIndex(i);
|
---|
680 | if (otherCount > 0) {
|
---|
681 | this.recordCountAtValue(otherCount, otherHistogram.valueFromIndex(i));
|
---|
682 | }
|
---|
683 | }
|
---|
684 | }
|
---|
685 | this.startTimeStampMsec = min(this.startTimeStampMsec, otherHistogram.startTimeStampMsec);
|
---|
686 | this.endTimeStampMsec = max(this.endTimeStampMsec, otherHistogram.endTimeStampMsec);
|
---|
687 | }
|
---|
688 | /**
|
---|
689 | * Get the count of recorded values at a specific value (to within the histogram resolution at the value level).
|
---|
690 | *
|
---|
691 | * @param value The value for which to provide the recorded count
|
---|
692 | * @return The total count of values recorded in the histogram within the value range that is
|
---|
693 | * {@literal >=} lowestEquivalentValue(<i>value</i>) and {@literal <=} highestEquivalentValue(<i>value</i>)
|
---|
694 | */
|
---|
695 | getCountAtValue(value) {
|
---|
696 | const index = min(max(0, this.countsArrayIndex(value)), this.countsArrayLength - 1);
|
---|
697 | return this.getCountAtIndex(index);
|
---|
698 | }
|
---|
699 | /**
|
---|
700 | * Subtract the contents of another histogram from this one.
|
---|
701 | * <p>
|
---|
702 | * The start/end timestamps of this histogram will remain unchanged.
|
---|
703 | *
|
---|
704 | * @param otherHistogram The other histogram.
|
---|
705 | * @throws ArrayIndexOutOfBoundsException (may throw) if values in otherHistogram's are higher than highestTrackableValue.
|
---|
706 | *
|
---|
707 | */
|
---|
708 | subtract(otherHistogram) {
|
---|
709 | const highestRecordableValue = this.valueFromIndex(this.countsArrayLength - 1);
|
---|
710 | if (!(otherHistogram instanceof JsHistogram)) {
|
---|
711 | // should be impossible to be in this situation but actually
|
---|
712 | // TypeScript has some flaws...
|
---|
713 | throw new Error("Cannot subtract a WASM histogram to a regular JS histogram");
|
---|
714 | }
|
---|
715 | if (highestRecordableValue < otherHistogram.maxValue) {
|
---|
716 | if (!this.autoResize) {
|
---|
717 | throw new Error("The other histogram includes values that do not fit in this histogram's range.");
|
---|
718 | }
|
---|
719 | this.resize(otherHistogram.maxValue);
|
---|
720 | }
|
---|
721 | if (this.bucketCount === otherHistogram.bucketCount &&
|
---|
722 | this.subBucketCount === otherHistogram.subBucketCount &&
|
---|
723 | this.unitMagnitude === otherHistogram.unitMagnitude) {
|
---|
724 | // optim
|
---|
725 | // Counts arrays are of the same length and meaning, so we can just iterate and add directly:
|
---|
726 | let observedOtherTotalCount = 0;
|
---|
727 | for (let i = 0; i < otherHistogram.countsArrayLength; i++) {
|
---|
728 | const otherCount = otherHistogram.getCountAtIndex(i);
|
---|
729 | if (otherCount > 0) {
|
---|
730 | this.addToCountAtIndex(i, -otherCount);
|
---|
731 | observedOtherTotalCount += otherCount;
|
---|
732 | }
|
---|
733 | }
|
---|
734 | this.setTotalCount(this.totalCount - observedOtherTotalCount);
|
---|
735 | }
|
---|
736 | else {
|
---|
737 | for (let i = 0; i < otherHistogram.countsArrayLength; i++) {
|
---|
738 | const otherCount = otherHistogram.getCountAtIndex(i);
|
---|
739 | if (otherCount > 0) {
|
---|
740 | const otherValue = otherHistogram.valueFromIndex(i);
|
---|
741 | if (this.getCountAtValue(otherValue) < otherCount) {
|
---|
742 | throw new Error("otherHistogram count (" +
|
---|
743 | otherCount +
|
---|
744 | ") at value " +
|
---|
745 | otherValue +
|
---|
746 | " is larger than this one's (" +
|
---|
747 | this.getCountAtValue(otherValue) +
|
---|
748 | ")");
|
---|
749 | }
|
---|
750 | this.recordCountAtValue(-otherCount, otherValue);
|
---|
751 | }
|
---|
752 | }
|
---|
753 | }
|
---|
754 | // With subtraction, the max and minNonZero values could have changed:
|
---|
755 | if (this.getCountAtValue(this.maxValue) <= 0 ||
|
---|
756 | this.getCountAtValue(this.minNonZeroValue) <= 0) {
|
---|
757 | this.establishInternalTackingValues();
|
---|
758 | }
|
---|
759 | }
|
---|
760 | establishInternalTackingValues(lengthToCover = this.countsArrayLength) {
|
---|
761 | this.maxValue = 0;
|
---|
762 | this.minNonZeroValue = Number.MAX_VALUE;
|
---|
763 | let maxIndex = -1;
|
---|
764 | let minNonZeroIndex = -1;
|
---|
765 | let observedTotalCount = 0;
|
---|
766 | for (let index = 0; index < lengthToCover; index++) {
|
---|
767 | const countAtIndex = this.getCountAtIndex(index);
|
---|
768 | if (countAtIndex > 0) {
|
---|
769 | observedTotalCount += countAtIndex;
|
---|
770 | maxIndex = index;
|
---|
771 | if (minNonZeroIndex == -1 && index != 0) {
|
---|
772 | minNonZeroIndex = index;
|
---|
773 | }
|
---|
774 | }
|
---|
775 | }
|
---|
776 | if (maxIndex >= 0) {
|
---|
777 | this.updatedMaxValue(this.highestEquivalentValue(this.valueFromIndex(maxIndex)));
|
---|
778 | }
|
---|
779 | if (minNonZeroIndex >= 0) {
|
---|
780 | this.updateMinNonZeroValue(this.valueFromIndex(minNonZeroIndex));
|
---|
781 | }
|
---|
782 | this.setTotalCount(observedTotalCount);
|
---|
783 | }
|
---|
784 | reset() {
|
---|
785 | this.clearCounts();
|
---|
786 | this.setTotalCount(0);
|
---|
787 | this.startTimeStampMsec = 0;
|
---|
788 | this.endTimeStampMsec = 0;
|
---|
789 | this.tag = Histogram_1.NO_TAG;
|
---|
790 | this.maxValue = 0;
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791 | this.minNonZeroValue = Number.MAX_SAFE_INTEGER;
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792 | }
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793 | destroy() {
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794 | // no op - not needed here
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795 | }
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796 | }
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797 | exports.JsHistogram = JsHistogram;
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798 | exports.default = JsHistogram;
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799 | //# sourceMappingURL=JsHistogram.js.map |
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