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// @flow
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import { write, read } from "@xtuc/ieee754";
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/**
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* According to https://webassembly.github.io/spec/binary/values.html#binary-float
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* n = 32/8
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*/
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export const NUMBER_OF_BYTE_F32 = 4;
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/**
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* According to https://webassembly.github.io/spec/binary/values.html#binary-float
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* n = 64/8
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*/
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export const NUMBER_OF_BYTE_F64 = 8;
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export const SINGLE_PRECISION_MANTISSA = 23;
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export const DOUBLE_PRECISION_MANTISSA = 52;
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export function encodeF32(v: number): Array<number> {
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const buffer = [];
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write(buffer, v, 0, true, SINGLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F32);
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return buffer;
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}
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export function encodeF64(v: number): Array<number> {
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const buffer = [];
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write(buffer, v, 0, true, DOUBLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F64);
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return buffer;
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}
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export function decodeF32(bytes: Array<Byte>): number {
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const buffer = Buffer.from(bytes);
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return read(buffer, 0, true, SINGLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F32);
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}
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export function decodeF64(bytes: Array<Byte>): number {
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const buffer = Buffer.from(bytes);
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return read(buffer, 0, true, DOUBLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F64);
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}
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