Uses BigInt to make BigFloats
Version vom
Dieses Skript sollte nicht direkt installiert werden. Es handelt sich hier um eine Bibliothek für andere Skripte, welche über folgenden Befehl in den Metadaten eines Skriptes eingebunden wird // @require https://update.greasyfork.org/scripts/563676/1740238/BigFloat.js
// ==UserScript==
// @name BigFloat
// @namespace -
// @version 1.0.0
// @description Uses BigInt to make BigFloats
// @author NotYou
// @grant none
// @license MIT
// ==/UserScript==
/*
* @typedef IStringifyOptions
* @property {boolean} [trailingZero=true]
* @property {boolean} [headZero=true]
* @property {number} [precision=3] recommended max value is 15. Higher values may result in incorrect result
* @property {boolean} [fixedPointNotation=false] if value is 12.3, precision is 3, but fixedPointNotation is true, then stringified value will be 12.300
*/
/*
* @typedef IToNumberOptions
* @property {number} [precision=3] recommended max value is 15. Higher values may result in incorrect result
*/
/*
* @typedef {number | `${number}` | BigInt | InstanceType<typeof BigFloat>} AcceptableValue
*/
!function() {
'use strict';
/* global BigInt */
class BigFloat {
/*
* @param {AcceptableValue} value
*/
constructor(value) {
const valueData = this._handleValue(value)
if (valueData === null) this._invalidValue(value)
/*
* @type {number}
*/
this._scale = valueData.scale
/*
* @type {number}
*/
this._value = valueData.value
}
/*
* @returns {string | number}
*/
[Symbol.toPrimitive](hint) {
if (hint === 'number') {
return this.toNumber()
}
return this.stringify()
}
/*
* @returns {string}
*/
get [Symbol.toStringTag]() {
return this.constructor.name
}
/*
* Throws an invalid value error. Stringifies value
*
* @param {AcceptableValue} value
* @returns {never}
*/
_invalidValue(value) {
let stringifiedValue = ''
try {
if (!Number.isFinite(value) || Number.isNaN(value) || typeof value === 'function') {
throw void 0
}
stringifiedValue = JSON.stringify(value)
} catch(_) {
stringifiedValue = String(value)
}
throw new Error(`"${stringifiedValue}" is invalid value and cannot be handled`)
}
/**
* Parses float number
*
* @param {number} value (must be float number)
* @returns { { value: string, scale: number } }
*/
_parseFloat(value) {
const parts = String(value).split('.')
return {
value: parts[0] + parts[1],
scale: -parts[1].length
}
}
/**
* Tries to return value as bigint and, also returns its scale
*
* @param {AcceptableValue} value
* @returns { { value: BigInt, scale: number } | null }
*/
_handleValue(value) {
const handleInt = value => {
return {
value: BigInt(value),
scale: 0
}
}
const handleFloat = value => {
const floatData = this._parseFloat(value)
return {
value: BigInt(floatData.value),
scale: floatData.scale
}
}
if (typeof value === 'bigint') {
return {
value,
scale: 0,
}
} else if (typeof value === 'number' && Number.isInteger(value)) { // is integer
return handleInt(value)
} else if (typeof value === 'number') { // is float
return handleFloat(value)
} else if (typeof value === 'string' && !isNaN(value)) { // is stringified number
const number = Number(value)
if (Number.isInteger(number)) {
return handleInt(number)
}
return handleFloat(number)
} else if (value instanceof this.constructor) {
return {
value: value.getRawValue(),
scale: value.getScale()
}
}
return null
}
/*
* Returns the value of the big float as a raw bigint
*
* @returns {bigint}
*/
getRawValue() {
return this._value
}
/*
* Returns the scale of the value
*
* For example, when: `value = 1234` and `scale = -1``
* Then result would be equal to 123.4
*
* @returns {number}
*/
getScale() {
return this._scale
}
/*
* @type {IStringifyOptions}
*/
_defaultStringifyOptions = {
trailingZero: true,
headZero: true,
precision: 3,
fixedPointNotation: false
}
/*
* Stringifies big float
*
* Note: toString is reserved for Symbol.toStringTag method
*
* @param {Optional<IStringifyOptions>} options
* @returns {string}
*/
stringify(options = {}) {
options = Object.assign({}, this._defaultStringifyOptions, options)
const scale = this.getScale()
const raw = this.getRawValue().toString()
if (scale === 0) {
if (!options.trailingZero) return raw
const zeros = options.fixedPointNotation
? options.precision
: 1
return raw + '.' + '0'.repeat(zeros)
}
const leftPart = raw.slice(0, scale)
let rightPart = raw.slice(scale)
rightPart = rightPart.slice(0, options.precision)
if (options.fixedPointNotation) {
rightPart = rightPart.padEnd(options.precision, '0')
}
if (leftPart === '' && options.headZero) {
return '0.' + rightPart
}
return leftPart + '.' + rightPart
}
/*
* @type {IToNumberOptions}
*/
_defaultToNumberOptions = {
precision: 3
}
/*
* Firstly stringfies the number using stringify (with default params) method, and then converts it to number
*
* @param {Optional<IToNumberOptions>} options
* @returns {number}
*/
toNumber(options) {
options = Object.assign({}, this._defaultToNumberOptions, options)
return Number(this.stringify(options))
}
/*
* @param {AcceptableValue} value Value that will be added or subtracted
* @param {0 | 1} sign zero for minus, one for plus
* @returns {this}
*/
_addOrSubtract(value, sign) {
const valueData = this._handleValue(value)
if (valueData === null) this._invalidValue(value)
let aValue = this._value
let aScale = this._scale
let bValue = valueData.value
let bScale = valueData.scale
if (aScale !== bScale) {
const minScale = Math.min(aScale, bScale)
if (aScale !== minScale) {
aValue *= 10n ** BigInt(aScale - minScale)
}
if (bScale !== minScale) {
bValue *= 10n ** BigInt(bScale - minScale)
}
aScale = minScale
}
this._value = sign === 1 ? aValue + bValue : aValue - bValue
this._scale = aScale
return this
}
/*
* @param {AcceptableValue} value
* @returns {this}
*/
add(value) {
return this._addOrSubtract(value, 1)
}
/*
* @param {AcceptableValue} value
* @returns {this}
*/
subtract(value) {
return this._addOrSubtract(value, -1)
}
/*
* @param {AcceptableValue} value
* @returns {this}
*/
multiply(value) {
const valueData = this._handleValue(value)
if (valueData === null) this._invalidValue(value)
this._value *= valueData.value
this._scale += valueData.scale
return this
}
/*
* @param {AcceptableValue} value
* @param {number} precision
* @returns {this}
*/
divide(value, precision = 3) {
const valueData = this._handleValue(value)
if (valueData === null) this._invalidValue(value)
if (valueData.value === 0n) {
throw new Error('Division by zero')
}
const factor = 10n ** BigInt(precision)
this._value = (this._value * factor) / valueData.value
this._scale = this._scale - valueData.scale - precision
return this
}
}
window.BigFloat = BigFloat
}();