source: trip-planner-front/node_modules/hdr-histogram-js/dist/packedarray/PackedArray.js@ 571e0df

Last change on this file since 571e0df was 6a3a178, checked in by Ema <ema_spirova@…>, 3 years ago

initial commit

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1"use strict";
2Object.defineProperty(exports, "__esModule", { value: true });
3exports.PackedArray = void 0;
4/*
5 * This is a TypeScript port of the original Java version, which was written by
6 * Gil Tene as described in
7 * https://github.com/HdrHistogram/HdrHistogram
8 * and released to the public domain, as explained at
9 * http://creativecommons.org/publicdomain/zero/1.0/
10 */
11const PackedArrayContext_1 = require("./PackedArrayContext");
12const NUMBER_OF_SETS = 8;
13const { pow, floor } = Math;
14/**
15 * A Packed array of signed 64 bit values, and supports {@link #get get()}, {@link #set set()},
16 * {@link #add add()} and {@link #increment increment()} operations on the logical contents of the array.
17 *
18 * An {@link PackedLongArray} Uses {@link PackedArrayContext} to track
19 * the array's logical contents. Contexts may be switched when a context requires resizing
20 * to complete logical array operations (get, set, add, increment). Contexts are
21 * established and used within critical sections in order to facilitate concurrent
22 * implementors.
23 *
24 */
25class PackedArray {
26 constructor(virtualLength, initialPhysicalLength = PackedArrayContext_1.MINIMUM_INITIAL_PACKED_ARRAY_CAPACITY) {
27 this.arrayContext = new PackedArrayContext_1.PackedArrayContext(virtualLength, initialPhysicalLength);
28 }
29 setVirtualLength(newVirtualArrayLength) {
30 if (newVirtualArrayLength < this.length()) {
31 throw new Error("Cannot set virtual length, as requested length " +
32 newVirtualArrayLength +
33 " is smaller than the current virtual length " +
34 this.length());
35 }
36 const currentArrayContext = this.arrayContext;
37 if (currentArrayContext.isPacked &&
38 currentArrayContext.determineTopLevelShiftForVirtualLength(newVirtualArrayLength) == currentArrayContext.getTopLevelShift()) {
39 // No changes to the array context contents is needed. Just change the virtual length.
40 currentArrayContext.setVirtualLength(newVirtualArrayLength);
41 return;
42 }
43 this.arrayContext = currentArrayContext.copyAndIncreaseSize(this.getPhysicalLength(), newVirtualArrayLength);
44 }
45 /**
46 * Get value at virtual index in the array
47 * @param index the virtual array index
48 * @return the array value at the virtual index given
49 */
50 get(index) {
51 let value = 0;
52 for (let byteNum = 0; byteNum < NUMBER_OF_SETS; byteNum++) {
53 let byteValueAtPackedIndex = 0;
54 // Deal with unpacked context:
55 if (!this.arrayContext.isPacked) {
56 return this.arrayContext.getAtUnpackedIndex(index);
57 }
58 // Context is packed:
59 const packedIndex = this.arrayContext.getPackedIndex(byteNum, index, false);
60 if (packedIndex < 0) {
61 return value;
62 }
63 byteValueAtPackedIndex =
64 this.arrayContext.getAtByteIndex(packedIndex) * pow(2, byteNum << 3);
65 value += byteValueAtPackedIndex;
66 }
67 return value;
68 }
69 /**
70 * Increment value at a virrual index in the array
71 * @param index virtual index of value to increment
72 */
73 increment(index) {
74 this.add(index, 1);
75 }
76 safeGetPackedIndexgetPackedIndex(setNumber, virtualIndex) {
77 //do {
78 //try {
79 return this.arrayContext.getPackedIndex(setNumber, virtualIndex, true);
80 /*} catch (ex) {
81 if (ex instanceof ResizeError) {
82 this.arrayContext.resizeArray(ex.newSize);
83 } else {
84 throw ex;
85 }
86 }*/
87 //} while (true);
88 }
89 /**
90 * Add to a value at a virtual index in the array
91 * @param index the virtual index of the value to be added to
92 * @param value the value to add
93 */
94 add(index, value) {
95 let remainingValueToAdd = value;
96 for (let byteNum = 0, byteShift = 0; byteNum < NUMBER_OF_SETS; byteNum++, byteShift += 8) {
97 // Deal with unpacked context:
98 if (!this.arrayContext.isPacked) {
99 this.arrayContext.addAndGetAtUnpackedIndex(index, value);
100 return;
101 }
102 // Context is packed:
103 const packedIndex = this.safeGetPackedIndexgetPackedIndex(byteNum, index);
104 const byteToAdd = remainingValueToAdd & 0xff;
105 const afterAddByteValue = this.arrayContext.addAtByteIndex(packedIndex, byteToAdd);
106 // Reduce remaining value to add by amount just added:
107 remainingValueToAdd -= byteToAdd;
108 remainingValueToAdd = remainingValueToAdd / pow(2, 8);
109 // Account for carry:
110 remainingValueToAdd += floor(afterAddByteValue / pow(2, 8));
111 if (remainingValueToAdd == 0) {
112 return; // nothing to add to higher magnitudes
113 }
114 }
115 }
116 /**
117 * Set the value at a virtual index in the array
118 * @param index the virtual index of the value to set
119 * @param value the value to set
120 */
121 set(index, value) {
122 let bytesAlreadySet = 0;
123 let valueForNextLevels = value;
124 for (let byteNum = 0; byteNum < NUMBER_OF_SETS; byteNum++) {
125 // Establish context within: critical section
126 // Deal with unpacked context:
127 if (!this.arrayContext.isPacked) {
128 this.arrayContext.setAtUnpackedIndex(index, value);
129 return;
130 }
131 // Context is packed:
132 if (valueForNextLevels == 0) {
133 // Special-case zeros to avoid inflating packed array for no reason
134 const packedIndex = this.arrayContext.getPackedIndex(byteNum, index, false);
135 if (packedIndex < 0) {
136 return; // no need to create entries for zero values if they don't already exist
137 }
138 }
139 // Make sure byte is populated:
140 const packedIndex = this.arrayContext.getPackedIndex(byteNum, index, true);
141 // Determine value to write, and prepare for next levels
142 const byteToWrite = valueForNextLevels & 0xff;
143 valueForNextLevels = floor(valueForNextLevels / pow(2, 8));
144 if (byteNum < bytesAlreadySet) {
145 // We want to avoid writing to the same byte twice when not doing so for the
146 // entire 64 bit value atomically, as doing so opens a race with e.g. concurrent
147 // adders. So dobn't actually write the byte if has been written before.
148 continue;
149 }
150 this.arrayContext.setAtByteIndex(packedIndex, byteToWrite);
151 bytesAlreadySet++;
152 }
153 }
154 /**
155 * Get the current physical length (in longs) of the array's backing storage
156 * @return the current physical length (in longs) of the array's current backing storage
157 */
158 getPhysicalLength() {
159 return this.arrayContext.physicalLength;
160 }
161 /**
162 * Get the (virtual) length of the array
163 * @return the (virtual) length of the array
164 */
165 length() {
166 return this.arrayContext.getVirtualLength();
167 }
168 /**
169 * Clear the array contents
170 */
171 clear() {
172 this.arrayContext.clear();
173 }
174 toString() {
175 let output = "PackedArray:\n";
176 output += this.arrayContext.toString();
177 return output;
178 }
179}
180exports.PackedArray = PackedArray;
181//# sourceMappingURL=PackedArray.js.map
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