# How to use decomposeFloat method in fast-check-monorepo

Best JavaScript code snippet using fast-check-monorepo

number.ts

Source:number.ts

`...72 // Using the remainder operation is only safe in the integer space.73 if (Math.abs(value) <= Number.MAX_SAFE_INTEGER && Number.isSafeInteger(multiple)) return value % multiple === 0;74 // It gets tricky for non-integer and especially small divisors. Using remainder does not work for small divisors, e.g.75 // `1 % 0.1 === 0.09999999999999995`. As a workaround, we convert both operands to integers first.76 const valueParts = decomposeFloat(value);77 const multipleParts = decomposeFloat(multiple);78 // Now sync the exponent, so we can only focus on the significands79 const exponent = Math.min(valueParts.exponent, multipleParts.exponent);80 const valueSignificand = significandForGivenExponent(valueParts, exponent);81 const multipleSignificand = significandForGivenExponent(multipleParts, exponent);82 return valueSignificand % multipleSignificand === ZERO;83}84// rewrite float to an integer and exponent, for example 123456789.222 to 123456789222e-385function decomposeFloat(n: number) {86 const [significand, exponent] = n.toExponential().split('e') as [string, string];87 // Now denormalize the significand to get rid of the decimal point.88 const [base, frac] = significand.split('.') as [string, string | undefined];89 return {90 significand: BIG(base + (frac || '')),91 exponent: +exponent - (frac ? frac.length : 0),92 };93}94function significandForGivenExponent(input: ReturnType<typeof decomposeFloat>, exponent: number) {95 return BIG(input.significand) * TEN ** BIG(input.exponent - exponent);96}97type Bound<T extends 'min' | 'max'> = {98 // The required fields for the given bound (min or max):99 [K in T | `\${T}Exclusive`]?: number;...`

FloatHelpers.spec.ts

Source:FloatHelpers.spec.ts

`...14 MIN_VALUE_32,15} from '../../../../../src/arbitrary/_internals/helpers/FloatHelpers';16describe('decomposeFloat', () => {17 it('should properly decompose basic values', () => {18 expect(decomposeFloat(0)).toEqual({ exponent: -126, significand: 0 });19 expect(decomposeFloat(1)).toEqual({ exponent: 0, significand: 1 });20 expect(decomposeFloat(128)).toEqual({ exponent: 7, significand: 1 });21 expect(decomposeFloat(201)).toEqual({ exponent: 7, significand: 1.5703125 });22 });23 it('should properly decompose negative values', () => {24 expect(decomposeFloat(-0)).toEqual({ exponent: -126, significand: -0 });25 expect(decomposeFloat(-1)).toEqual({ exponent: 0, significand: -1 });26 });27 it('should properly decompose extreme values', () => {28 expect(decomposeFloat(MAX_VALUE_32)).toEqual({ exponent: 127, significand: 1 + (2 ** 23 - 1) / 2 ** 23 });29 expect(decomposeFloat(MIN_VALUE_32)).toEqual({ exponent: -126, significand: 2 ** -23 });30 expect(decomposeFloat(EPSILON_32)).toEqual({ exponent: -23, significand: 1 });31 expect(decomposeFloat(1 + EPSILON_32)).toEqual({ exponent: 0, significand: 1 + 2 ** -23 });32 });33 it('should decompose a 32-bit float into its equivalent (significand, exponent)', () => {34 fc.assert(35 fc.property(float32raw(), (f32) => {36 // Arrange37 fc.pre(isFiniteNotNaN32bits(f32));38 // Act39 const { exponent, significand } = decomposeFloat(f32);40 // Assert41 expect(significand * 2 ** exponent).toBe(f32);42 })43 );44 });45});46describe('floatToIndex', () => {47 it('should properly compute indexes', () => {48 expect(floatToIndex(0)).toBe(0);49 expect(floatToIndex(MIN_VALUE_32)).toBe(1);50 expect(floatToIndex(2 * MIN_VALUE_32)).toBe(2);51 expect(floatToIndex(3 * MIN_VALUE_32)).toBe(3);52 // EPSILON_32 === 1. * 2**-23 --> m = 1, e = -2353 // index(EPSILON_32) = 2**24 + (-23 - (-126) -1) * 2**23...`

FloatHelpers.ts

Source:FloatHelpers.ts

`...30 * @param f - 32-bit floating point number to be decomposed into (significand, exponent)31 *32 * @internal33 */34export function decomposeFloat(f: number): { exponent: number; significand: number } {35 // 1 => significand 0b1 - exponent 1 (will be preferred)36 // => significand 0b0.1 - exponent 237 const maxSignificand = 1 + (2 ** 23 - 1) / 2 ** 23;38 for (let exponent = -126; exponent !== 128; ++exponent) {39 const powExponent = 2 ** exponent;40 const maxForExponent = maxSignificand * powExponent;41 if (Math.abs(f) <= maxForExponent) {42 return { exponent, significand: f / powExponent };43 }44 }45 return { exponent: safeNaN, significand: safeNaN };46}47/** @internal */48function indexInFloatFromDecomp(exponent: number, significand: number) {49 // WARNING: significand >= 050 // By construct of significand in decomposeFloat,51 // significand is always max-ed.52 // The float close to zero are the only one having a significand <1, they also have an exponent of -126.53 // They are in range: [2**(-126) * 2**(-23), 2**(-126) * (2 - 2 ** 23)]54 // In other words there are 2**24 elements in that range if we include zero.55 // All other ranges (other exponents) have a length of 2**23 elements.56 if (exponent === -126) {57 return significand * 0x800000; // significand * 2**2358 }59 // Offset due to exp = -126 + Offset of previous exp (excl. -126) + Offset in current exp60 // 2**24 + (exponent - (-126) -1) * 2**23 + (significand - 1) * 2**2361 return (exponent + 127) * 0x800000 + (significand - 1) * 0x800000;62}63/**64 * Compute the index of f relative to other available 32-bit floating point numbers65 * Rq: Produces negative indexes for negative floats66 *67 * @param f - 32-bit floating point number68 *69 * @internal70 */71export function floatToIndex(f: number): number {72 if (f === safePositiveInfinity) {73 return INDEX_POSITIVE_INFINITY;74 }75 if (f === safeNegativeInfinity) {76 return INDEX_NEGATIVE_INFINITY;77 }78 const decomp = decomposeFloat(f);79 const exponent = decomp.exponent;80 const significand = decomp.significand;81 if (safeNumberIsNaN(exponent) || safeNumberIsNaN(significand) || !safeNumberIsInteger(significand * 0x800000)) {82 return safeNaN;83 }84 if (f > 0 || (f === 0 && 1 / f === safePositiveInfinity)) {85 return indexInFloatFromDecomp(exponent, significand);86 } else {87 return -indexInFloatFromDecomp(exponent, -significand) - 1;88 }89}90/**91 * Compute the 32-bit floating point number corresponding to the provided indexes92 *...`

Using AI Code Generation

`1const fc = require("fast-check");2const { decomposeFloat } = require("fast-check/lib/types/float/FloatArbitrary");3const { FloatNextConstraints } = require("fast-check/lib/types/float/FloatNextConstraints");4const { FloatNextConstraintsBuilder } = require("fast-check/lib/types/float/FloatNextConstraintsBuilder");5const { FloatNextConstraintsBuilderWithMin } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithMin");6const { FloatNextConstraintsBuilderWithMax } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithMax");7const { FloatNextConstraintsBuilderWithNext } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithNext");8const { FloatNextConstraintsBuilderWithBias } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBias");9const { FloatNextConstraintsBuilderWithBiasAndMin } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBiasAndMin");10const { FloatNextConstraintsBuilderWithBiasAndMax } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBiasAndMax");11const { FloatNextConstraintsBuilderWithBiasAndNext } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBiasAndNext");12const { FloatNextConstraintsBuilderWithBiasAndNextAndMin } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBiasAndNextAndMin");13const { FloatNextConstraintsBuilderWithBiasAndNextAndMax } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBiasAndNextAndMax");14const { FloatNextConstraintsBuilderWithBiasAndNextAndNext } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBiasAndNextAndNext");15const { FloatNextConstraintsBuilderWithBiasAndNextAndNextAndMin } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBiasAndNextAndNextAndMin");16const { FloatNextConstraintsBuilderWithBiasAndNextAndNextAndMax } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBiasAndNextAndNextAndMax");17const { FloatNextConstraintsBuilderWithBiasAndNextAndNextAndNext } = require("fast-check/lib/types/float/FloatNextConstraintsBuilderWithBiasAndNextAndNextAndNext");18const { FloatNextConstraintsBuilderWithBiasAndNextAndNextAndNextAndMin } =`

Using AI Code Generation

`1const { decomposeFloat } = require("fast-check");2const fc = require("fast-check");3const { decomposeFloat } = require("fast-check");4fc.assert(5 fc.property(fc.float(), (f) => {6 const { exponent, significand } = decomposeFloat(f);7 return f === significand * 2 ** exponent;8 })9);10const { decomposeFloat } = require("fast-check");11const fc = require("fast-check");12const { decomposeFloat } = require("fast-check");13fc.assert(14 fc.property(fc.float(), (f) => {15 const { exponent, significand } = decomposeFloat(f);16 return f === significand * 2 ** exponent;17 })18);19const { decomposeFloat } = require("fast-check");20const fc = require("fast-check");21const { decomposeFloat } = require("fast-check");22fc.assert(23 fc.property(fc.float(), (f) => {24 const { exponent, significand } = decomposeFloat(f);25 return f === significand * 2 ** exponent;26 })27);28const { decomposeFloat } = require("fast-check");29const fc = require("fast-check");30const { decomposeFloat } = require("fast-check");31fc.assert(32 fc.property(fc.float(), (f) => {33 const { exponent, significand } = decomposeFloat(f);34 return f === significand * 2 ** exponent;35 })36);37const { decomposeFloat } = require("fast-check");38const fc = require("fast-check");39const { decomposeFloat } = require("fast-check");40fc.assert(41 fc.property(fc.float(), (f) => {42 const { exponent, significand } = decomposeFloat(f);43 return f === significand * 2 ** exponent;44 })45);46const { decomposeFloat } = require("fast-check");47const fc = require("fast-check");48const { decomposeFloat } = require("fast-check");49fc.assert(50 fc.property(fc.float(), (f) => {`

Using AI Code Generation

`1 throw err;2 at Function.Module._resolveFilename (internal/modules/cjs/loader.js:636:15)3 at Function.Module._load (internal/modules/cjs/loader.js:562:25)4 at Module.require (internal/modules/cjs/loader.js:692:17)5 at require (internal/modules/cjs/helpers.js:25:18)6 at Object.<anonymous> (/Users/.../workspace/fast-check-monorepo/fast-check/test3.js:1:18)7 at Module._compile (internal/modules/cjs/loader.js:778:30)8 at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)9 at Module.load (internal/modules/cjs/loader.js:653:32)10 at tryModuleLoad (internal/modules/cjs/loader.js:593:12)11 at Function.Module._load (internal/modules/cjs/loader.js:585:3)12 throw err;13 at Function.Module._resolveFilename (internal/modules/cjs/loader.js:636:15)14 at Function.Module._load (internal/modules/cjs/loader.js:562:25)15 at Module.require (internal/modules/cjs/loader.js:`

Using AI Code Generation

`1const fc = require('fast-check');2const { decomposeFloat } = require('fast-check');3const { assert } = require('chai');4const assert = require('assert');5const { expect } = require('chai');6const { should } = require('chai');7const chai = require('chai');8const chaiAsPromised = require("chai-as-promised");9chai.use(chaiAsPromised);10chai.should();11describe('decomposeFloat', () => {12 it('should decompose a number into a sign, an exponent and a significand', () =>13 fc.assert(14 fc.property(fc.float(), f => {15 const { sign, exponent, significand } = decomposeFloat(f);16 expect(sign).to.be.oneOf([-1, 1]);17 expect(exponent).to.be.a('number');18 expect(significand).to.be.a('number');19 expect(f).to.equal(sign * significand * Math.pow(2, exponent));20 })21 ));22});23const fc = require('fast-check');24const { decomposeFloat } = require('fast-check');25const { assert } = require('chai');26const assert = require('assert');27const { expect } = require('chai');28const { should } = require('chai');29const chai = require('chai');30const chaiAsPromised = require("chai-as-promised");31chai.use(chaiAsPromised);32chai.should();33describe('decomposeFloat', () => {34 it('should decompose a number into a sign, an exponent and a significand', () =>35 fc.assert(36 fc.property(fc.float(), f => {37 const { sign, exponent, significand } = decomposeFloat(f);38 expect(sign).to.be.oneOf([-1, 1]);39 expect(exponent).to.be.a('number');40 expect(significand).to.be.a('number');41 expect(f).to.equal(sign * significand * Math.pow(2, exponent));42 })43 ));44});45const fc = require('fast-check');46const { decomposeFloat } = require('fast-check');47const { assert }`

Using AI Code Generation

`1const fc = require('fast-check');2const { decomposeFloat } = require('fast-check-monorepo');3const test3 = (value) => {4 console.log('value : ' + value);5 console.log('decomposeFloat(value) : ' + decomposeFloat(value));6}7test3(0.1);8test3(0.2);9test3(0.3);10test3(0.4);11test3(0.5);12test3(0.6);13test3(0.7);14test3(0.8);15test3(0.9);16test3(1.1);17test3(1.2);18test3(1.3);19test3(1.4);20test3(1.5);21test3(1.6);22test3(1.7);23test3(1.8);24test3(1.9);25decomposeFloat(value) : 0.1000000000000000126decomposeFloat(value) : 0.2000000000000000127decomposeFloat(value) : 0.3000000000000000428decomposeFloat(value) : 0.4000000000000000229decomposeFloat(value) : 0.530decomposeFloat(value) : 0.6000000000000000931decomposeFloat(value) : 0.7000000000000000732decomposeFloat(value) : 0.8000000000000000433decomposeFloat(value) : 0.9000000000000000234decomposeFloat(value) : 1.100000000000000135decomposeFloat(value) : 1.2000000000000002`

Using AI Code Generation

`1const fc = require("fast-check");2const { decomposeFloat } = require("@fast-check/arbitrary/float");3const test3 = () => {4 console.log("test3");5 const decomposed = decomposeFloat(0.000001);6 console.log(decomposed);7};8test3();9const fc = require("fast-check");10const { decomposeFloat } = require("@fast-check/arbitrary/float");11const test4 = () => {12 console.log("test4");`

Using AI Code Generation

`1const fc = require('fast-check');2const decomposeFloat = require('fast-check/lib/utils/FloatDecomposition').decomposeFloat;3function decomposeAndReconstructFloat(float) {4 let result = false;5 const decomposedFloat = decomposeFloat(float);6 const mantissa = decomposedFloat.mantissa;7 const exponent = decomposedFloat.exponent;8 const reconstructedFloat = mantissa * Math.pow(2, exponent);9 if (float === reconstructedFloat) {10 result = true;11 }12 return result;13}14const property = fc.property(fc.float(), (float) => {15 return decomposeAndReconstructFloat(float);16});17describe('decompose and reconstruct float', () => {18 it('should pass', () => {19 fc.assert(property);20 });21});`

Using AI Code Generation

`1var fc = require('fast-check');2var assert = require('assert');3function decomposeFloat(f) {4 var sign = f < 0 ? -1 : 1;5 if (f === 0) return [0, 0, 0];6 var exponent = Math.floor(Math.log2(Math.abs(f)));7 var mantissa = Math.abs(f) * Math.pow(2, -exponent);8 return [sign, exponent, mantissa];9}10function composeFloat(sign, exponent, mantissa) {11 if (sign === 0) return 0;12 return sign * mantissa * Math.pow(2, exponent);13}14function testDecomposeFloat(f) {15 var [sign, exponent, mantissa] = decomposeFloat(f);16 var f2 = composeFloat(sign, exponent, mantissa);17 return f2 === f;18}19var result = fc.assert(fc.property(fc.float(), testDecomposeFloat));20console.log(result);21var fc = require('fast-check');22var assert = require('assert');23function decomposeFloat(f) {24 var sign = f < 0 ? -1 : 1;25 if (f === 0) return [0, 0, 0];26 var exponent = Math.floor(Math.log2(Math.abs(f)));`

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