924 lines
21 KiB
JavaScript
924 lines
21 KiB
JavaScript
/*
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* big.js v5.2.2
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* A small, fast, easy-to-use library for arbitrary-precision decimal arithmetic.
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* Copyright (c) 2018 Michael Mclaughlin <M8ch88l@gmail.com>
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* https://github.com/MikeMcl/big.js/LICENCE
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*/
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/************************************** EDITABLE DEFAULTS *****************************************/
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// The default values below must be integers within the stated ranges.
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/*
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* The maximum number of decimal places (DP) of the results of operations involving division:
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* div and sqrt, and pow with negative exponents.
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*/
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var DP = 20, // 0 to MAX_DP
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/*
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* The rounding mode (RM) used when rounding to the above decimal places.
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*
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* 0 Towards zero (i.e. truncate, no rounding). (ROUND_DOWN)
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* 1 To nearest neighbour. If equidistant, round up. (ROUND_HALF_UP)
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* 2 To nearest neighbour. If equidistant, to even. (ROUND_HALF_EVEN)
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* 3 Away from zero. (ROUND_UP)
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*/
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RM = 1, // 0, 1, 2 or 3
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// The maximum value of DP and Big.DP.
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MAX_DP = 1E6, // 0 to 1000000
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// The maximum magnitude of the exponent argument to the pow method.
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MAX_POWER = 1E6, // 1 to 1000000
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/*
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* The negative exponent (NE) at and beneath which toString returns exponential notation.
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* (JavaScript numbers: -7)
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* -1000000 is the minimum recommended exponent value of a Big.
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*/
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NE = -7, // 0 to -1000000
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/*
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* The positive exponent (PE) at and above which toString returns exponential notation.
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* (JavaScript numbers: 21)
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* 1000000 is the maximum recommended exponent value of a Big.
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* (This limit is not enforced or checked.)
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*/
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PE = 21, // 0 to 1000000
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/**************************************************************************************************/
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// Error messages.
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NAME = '[big.js] ',
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INVALID = NAME + 'Invalid ',
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INVALID_DP = INVALID + 'decimal places',
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INVALID_RM = INVALID + 'rounding mode',
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DIV_BY_ZERO = NAME + 'Division by zero',
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// The shared prototype object.
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P = {},
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UNDEFINED = void 0,
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NUMERIC = /^-?(\d+(\.\d*)?|\.\d+)(e[+-]?\d+)?$/i;
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/*
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* Create and return a Big constructor.
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*
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*/
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function _Big_() {
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/*
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* The Big constructor and exported function.
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* Create and return a new instance of a Big number object.
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*
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* n {number|string|Big} A numeric value.
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*/
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function Big(n) {
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var x = this;
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// Enable constructor usage without new.
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if (!(x instanceof Big)) return n === UNDEFINED ? _Big_() : new Big(n);
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// Duplicate.
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if (n instanceof Big) {
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x.s = n.s;
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x.e = n.e;
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x.c = n.c.slice();
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} else {
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parse(x, n);
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}
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/*
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* Retain a reference to this Big constructor, and shadow Big.prototype.constructor which
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* points to Object.
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*/
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x.constructor = Big;
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}
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Big.prototype = P;
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Big.DP = DP;
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Big.RM = RM;
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Big.NE = NE;
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Big.PE = PE;
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Big.version = '5.2.2';
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return Big;
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}
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/*
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* Parse the number or string value passed to a Big constructor.
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*
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* x {Big} A Big number instance.
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* n {number|string} A numeric value.
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*/
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function parse(x, n) {
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var e, i, nl;
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// Minus zero?
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if (n === 0 && 1 / n < 0) n = '-0';
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else if (!NUMERIC.test(n += '')) throw Error(INVALID + 'number');
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// Determine sign.
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x.s = n.charAt(0) == '-' ? (n = n.slice(1), -1) : 1;
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// Decimal point?
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if ((e = n.indexOf('.')) > -1) n = n.replace('.', '');
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// Exponential form?
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if ((i = n.search(/e/i)) > 0) {
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// Determine exponent.
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if (e < 0) e = i;
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e += +n.slice(i + 1);
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n = n.substring(0, i);
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} else if (e < 0) {
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// Integer.
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e = n.length;
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}
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nl = n.length;
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// Determine leading zeros.
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for (i = 0; i < nl && n.charAt(i) == '0';) ++i;
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if (i == nl) {
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// Zero.
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x.c = [x.e = 0];
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} else {
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// Determine trailing zeros.
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for (; nl > 0 && n.charAt(--nl) == '0';);
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x.e = e - i - 1;
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x.c = [];
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// Convert string to array of digits without leading/trailing zeros.
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for (e = 0; i <= nl;) x.c[e++] = +n.charAt(i++);
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}
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return x;
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}
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/*
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* Round Big x to a maximum of dp decimal places using rounding mode rm.
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* Called by stringify, P.div, P.round and P.sqrt.
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*
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* x {Big} The Big to round.
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* dp {number} Integer, 0 to MAX_DP inclusive.
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* rm {number} 0, 1, 2 or 3 (DOWN, HALF_UP, HALF_EVEN, UP)
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* [more] {boolean} Whether the result of division was truncated.
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*/
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function round(x, dp, rm, more) {
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var xc = x.c,
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i = x.e + dp + 1;
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if (i < xc.length) {
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if (rm === 1) {
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// xc[i] is the digit after the digit that may be rounded up.
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more = xc[i] >= 5;
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} else if (rm === 2) {
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more = xc[i] > 5 || xc[i] == 5 &&
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(more || i < 0 || xc[i + 1] !== UNDEFINED || xc[i - 1] & 1);
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} else if (rm === 3) {
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more = more || !!xc[0];
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} else {
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more = false;
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if (rm !== 0) throw Error(INVALID_RM);
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}
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if (i < 1) {
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xc.length = 1;
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if (more) {
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// 1, 0.1, 0.01, 0.001, 0.0001 etc.
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x.e = -dp;
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xc[0] = 1;
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} else {
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// Zero.
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xc[0] = x.e = 0;
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}
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} else {
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// Remove any digits after the required decimal places.
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xc.length = i--;
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// Round up?
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if (more) {
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// Rounding up may mean the previous digit has to be rounded up.
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for (; ++xc[i] > 9;) {
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xc[i] = 0;
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if (!i--) {
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++x.e;
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xc.unshift(1);
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}
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}
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}
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// Remove trailing zeros.
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for (i = xc.length; !xc[--i];) xc.pop();
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}
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} else if (rm < 0 || rm > 3 || rm !== ~~rm) {
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throw Error(INVALID_RM);
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}
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return x;
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}
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/*
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* Return a string representing the value of Big x in normal or exponential notation.
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* Handles P.toExponential, P.toFixed, P.toJSON, P.toPrecision, P.toString and P.valueOf.
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*
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* x {Big}
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* id? {number} Caller id.
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* 1 toExponential
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* 2 toFixed
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* 3 toPrecision
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* 4 valueOf
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* n? {number|undefined} Caller's argument.
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* k? {number|undefined}
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*/
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function stringify(x, id, n, k) {
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var e, s,
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Big = x.constructor,
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z = !x.c[0];
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if (n !== UNDEFINED) {
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if (n !== ~~n || n < (id == 3) || n > MAX_DP) {
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throw Error(id == 3 ? INVALID + 'precision' : INVALID_DP);
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}
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x = new Big(x);
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// The index of the digit that may be rounded up.
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n = k - x.e;
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// Round?
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if (x.c.length > ++k) round(x, n, Big.RM);
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// toFixed: recalculate k as x.e may have changed if value rounded up.
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if (id == 2) k = x.e + n + 1;
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// Append zeros?
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for (; x.c.length < k;) x.c.push(0);
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}
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e = x.e;
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s = x.c.join('');
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n = s.length;
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// Exponential notation?
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if (id != 2 && (id == 1 || id == 3 && k <= e || e <= Big.NE || e >= Big.PE)) {
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s = s.charAt(0) + (n > 1 ? '.' + s.slice(1) : '') + (e < 0 ? 'e' : 'e+') + e;
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// Normal notation.
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} else if (e < 0) {
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for (; ++e;) s = '0' + s;
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s = '0.' + s;
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} else if (e > 0) {
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if (++e > n) for (e -= n; e--;) s += '0';
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else if (e < n) s = s.slice(0, e) + '.' + s.slice(e);
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} else if (n > 1) {
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s = s.charAt(0) + '.' + s.slice(1);
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}
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return x.s < 0 && (!z || id == 4) ? '-' + s : s;
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}
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// Prototype/instance methods
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/*
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* Return a new Big whose value is the absolute value of this Big.
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*/
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P.abs = function () {
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var x = new this.constructor(this);
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x.s = 1;
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return x;
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};
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/*
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* Return 1 if the value of this Big is greater than the value of Big y,
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* -1 if the value of this Big is less than the value of Big y, or
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* 0 if they have the same value.
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*/
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P.cmp = function (y) {
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var isneg,
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x = this,
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xc = x.c,
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yc = (y = new x.constructor(y)).c,
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i = x.s,
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j = y.s,
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k = x.e,
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l = y.e;
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// Either zero?
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if (!xc[0] || !yc[0]) return !xc[0] ? !yc[0] ? 0 : -j : i;
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// Signs differ?
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if (i != j) return i;
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isneg = i < 0;
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// Compare exponents.
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if (k != l) return k > l ^ isneg ? 1 : -1;
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j = (k = xc.length) < (l = yc.length) ? k : l;
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// Compare digit by digit.
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for (i = -1; ++i < j;) {
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if (xc[i] != yc[i]) return xc[i] > yc[i] ^ isneg ? 1 : -1;
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}
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// Compare lengths.
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return k == l ? 0 : k > l ^ isneg ? 1 : -1;
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};
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/*
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* Return a new Big whose value is the value of this Big divided by the value of Big y, rounded,
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* if necessary, to a maximum of Big.DP decimal places using rounding mode Big.RM.
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*/
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P.div = function (y) {
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var x = this,
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Big = x.constructor,
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a = x.c, // dividend
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b = (y = new Big(y)).c, // divisor
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k = x.s == y.s ? 1 : -1,
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dp = Big.DP;
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if (dp !== ~~dp || dp < 0 || dp > MAX_DP) throw Error(INVALID_DP);
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// Divisor is zero?
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if (!b[0]) throw Error(DIV_BY_ZERO);
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// Dividend is 0? Return +-0.
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if (!a[0]) return new Big(k * 0);
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var bl, bt, n, cmp, ri,
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bz = b.slice(),
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ai = bl = b.length,
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al = a.length,
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r = a.slice(0, bl), // remainder
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rl = r.length,
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q = y, // quotient
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qc = q.c = [],
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qi = 0,
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d = dp + (q.e = x.e - y.e) + 1; // number of digits of the result
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q.s = k;
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k = d < 0 ? 0 : d;
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// Create version of divisor with leading zero.
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bz.unshift(0);
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// Add zeros to make remainder as long as divisor.
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for (; rl++ < bl;) r.push(0);
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do {
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// n is how many times the divisor goes into current remainder.
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for (n = 0; n < 10; n++) {
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// Compare divisor and remainder.
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if (bl != (rl = r.length)) {
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cmp = bl > rl ? 1 : -1;
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} else {
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for (ri = -1, cmp = 0; ++ri < bl;) {
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if (b[ri] != r[ri]) {
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cmp = b[ri] > r[ri] ? 1 : -1;
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break;
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}
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}
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}
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// If divisor < remainder, subtract divisor from remainder.
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if (cmp < 0) {
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// Remainder can't be more than 1 digit longer than divisor.
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// Equalise lengths using divisor with extra leading zero?
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for (bt = rl == bl ? b : bz; rl;) {
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if (r[--rl] < bt[rl]) {
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ri = rl;
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for (; ri && !r[--ri];) r[ri] = 9;
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--r[ri];
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r[rl] += 10;
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}
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r[rl] -= bt[rl];
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}
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for (; !r[0];) r.shift();
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} else {
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break;
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}
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}
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// Add the digit n to the result array.
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qc[qi++] = cmp ? n : ++n;
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// Update the remainder.
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if (r[0] && cmp) r[rl] = a[ai] || 0;
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else r = [a[ai]];
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} while ((ai++ < al || r[0] !== UNDEFINED) && k--);
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// Leading zero? Do not remove if result is simply zero (qi == 1).
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if (!qc[0] && qi != 1) {
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// There can't be more than one zero.
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qc.shift();
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q.e--;
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}
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// Round?
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if (qi > d) round(q, dp, Big.RM, r[0] !== UNDEFINED);
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return q;
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};
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/*
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* Return true if the value of this Big is equal to the value of Big y, otherwise return false.
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*/
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P.eq = function (y) {
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return !this.cmp(y);
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};
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/*
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* Return true if the value of this Big is greater than the value of Big y, otherwise return
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* false.
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*/
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P.gt = function (y) {
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return this.cmp(y) > 0;
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};
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/*
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* Return true if the value of this Big is greater than or equal to the value of Big y, otherwise
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* return false.
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*/
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P.gte = function (y) {
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return this.cmp(y) > -1;
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};
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/*
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* Return true if the value of this Big is less than the value of Big y, otherwise return false.
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*/
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P.lt = function (y) {
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return this.cmp(y) < 0;
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};
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/*
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* Return true if the value of this Big is less than or equal to the value of Big y, otherwise
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* return false.
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*/
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P.lte = function (y) {
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return this.cmp(y) < 1;
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};
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/*
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* Return a new Big whose value is the value of this Big minus the value of Big y.
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*/
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P.minus = P.sub = function (y) {
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var i, j, t, xlty,
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x = this,
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Big = x.constructor,
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a = x.s,
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b = (y = new Big(y)).s;
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// Signs differ?
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if (a != b) {
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y.s = -b;
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return x.plus(y);
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}
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var xc = x.c.slice(),
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xe = x.e,
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yc = y.c,
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ye = y.e;
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// Either zero?
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if (!xc[0] || !yc[0]) {
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// y is non-zero? x is non-zero? Or both are zero.
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return yc[0] ? (y.s = -b, y) : new Big(xc[0] ? x : 0);
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}
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// Determine which is the bigger number. Prepend zeros to equalise exponents.
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if (a = xe - ye) {
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if (xlty = a < 0) {
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a = -a;
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t = xc;
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} else {
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ye = xe;
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t = yc;
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}
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t.reverse();
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for (b = a; b--;) t.push(0);
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t.reverse();
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} else {
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// Exponents equal. Check digit by digit.
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j = ((xlty = xc.length < yc.length) ? xc : yc).length;
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for (a = b = 0; b < j; b++) {
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if (xc[b] != yc[b]) {
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xlty = xc[b] < yc[b];
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break;
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}
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}
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}
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// x < y? Point xc to the array of the bigger number.
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if (xlty) {
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t = xc;
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xc = yc;
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yc = t;
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y.s = -y.s;
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}
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/*
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* Append zeros to xc if shorter. No need to add zeros to yc if shorter as subtraction only
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* needs to start at yc.length.
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*/
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if ((b = (j = yc.length) - (i = xc.length)) > 0) for (; b--;) xc[i++] = 0;
|
|
|
|
// Subtract yc from xc.
|
|
for (b = i; j > a;) {
|
|
if (xc[--j] < yc[j]) {
|
|
for (i = j; i && !xc[--i];) xc[i] = 9;
|
|
--xc[i];
|
|
xc[j] += 10;
|
|
}
|
|
|
|
xc[j] -= yc[j];
|
|
}
|
|
|
|
// Remove trailing zeros.
|
|
for (; xc[--b] === 0;) xc.pop();
|
|
|
|
// Remove leading zeros and adjust exponent accordingly.
|
|
for (; xc[0] === 0;) {
|
|
xc.shift();
|
|
--ye;
|
|
}
|
|
|
|
if (!xc[0]) {
|
|
|
|
// n - n = +0
|
|
y.s = 1;
|
|
|
|
// Result must be zero.
|
|
xc = [ye = 0];
|
|
}
|
|
|
|
y.c = xc;
|
|
y.e = ye;
|
|
|
|
return y;
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a new Big whose value is the value of this Big modulo the value of Big y.
|
|
*/
|
|
P.mod = function (y) {
|
|
var ygtx,
|
|
x = this,
|
|
Big = x.constructor,
|
|
a = x.s,
|
|
b = (y = new Big(y)).s;
|
|
|
|
if (!y.c[0]) throw Error(DIV_BY_ZERO);
|
|
|
|
x.s = y.s = 1;
|
|
ygtx = y.cmp(x) == 1;
|
|
x.s = a;
|
|
y.s = b;
|
|
|
|
if (ygtx) return new Big(x);
|
|
|
|
a = Big.DP;
|
|
b = Big.RM;
|
|
Big.DP = Big.RM = 0;
|
|
x = x.div(y);
|
|
Big.DP = a;
|
|
Big.RM = b;
|
|
|
|
return this.minus(x.times(y));
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a new Big whose value is the value of this Big plus the value of Big y.
|
|
*/
|
|
P.plus = P.add = function (y) {
|
|
var t,
|
|
x = this,
|
|
Big = x.constructor,
|
|
a = x.s,
|
|
b = (y = new Big(y)).s;
|
|
|
|
// Signs differ?
|
|
if (a != b) {
|
|
y.s = -b;
|
|
return x.minus(y);
|
|
}
|
|
|
|
var xe = x.e,
|
|
xc = x.c,
|
|
ye = y.e,
|
|
yc = y.c;
|
|
|
|
// Either zero? y is non-zero? x is non-zero? Or both are zero.
|
|
if (!xc[0] || !yc[0]) return yc[0] ? y : new Big(xc[0] ? x : a * 0);
|
|
|
|
xc = xc.slice();
|
|
|
|
// Prepend zeros to equalise exponents.
|
|
// Note: reverse faster than unshifts.
|
|
if (a = xe - ye) {
|
|
if (a > 0) {
|
|
ye = xe;
|
|
t = yc;
|
|
} else {
|
|
a = -a;
|
|
t = xc;
|
|
}
|
|
|
|
t.reverse();
|
|
for (; a--;) t.push(0);
|
|
t.reverse();
|
|
}
|
|
|
|
// Point xc to the longer array.
|
|
if (xc.length - yc.length < 0) {
|
|
t = yc;
|
|
yc = xc;
|
|
xc = t;
|
|
}
|
|
|
|
a = yc.length;
|
|
|
|
// Only start adding at yc.length - 1 as the further digits of xc can be left as they are.
|
|
for (b = 0; a; xc[a] %= 10) b = (xc[--a] = xc[a] + yc[a] + b) / 10 | 0;
|
|
|
|
// No need to check for zero, as +x + +y != 0 && -x + -y != 0
|
|
|
|
if (b) {
|
|
xc.unshift(b);
|
|
++ye;
|
|
}
|
|
|
|
// Remove trailing zeros.
|
|
for (a = xc.length; xc[--a] === 0;) xc.pop();
|
|
|
|
y.c = xc;
|
|
y.e = ye;
|
|
|
|
return y;
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a Big whose value is the value of this Big raised to the power n.
|
|
* If n is negative, round to a maximum of Big.DP decimal places using rounding
|
|
* mode Big.RM.
|
|
*
|
|
* n {number} Integer, -MAX_POWER to MAX_POWER inclusive.
|
|
*/
|
|
P.pow = function (n) {
|
|
var x = this,
|
|
one = new x.constructor(1),
|
|
y = one,
|
|
isneg = n < 0;
|
|
|
|
if (n !== ~~n || n < -MAX_POWER || n > MAX_POWER) throw Error(INVALID + 'exponent');
|
|
if (isneg) n = -n;
|
|
|
|
for (;;) {
|
|
if (n & 1) y = y.times(x);
|
|
n >>= 1;
|
|
if (!n) break;
|
|
x = x.times(x);
|
|
}
|
|
|
|
return isneg ? one.div(y) : y;
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a new Big whose value is the value of this Big rounded using rounding mode rm
|
|
* to a maximum of dp decimal places, or, if dp is negative, to an integer which is a
|
|
* multiple of 10**-dp.
|
|
* If dp is not specified, round to 0 decimal places.
|
|
* If rm is not specified, use Big.RM.
|
|
*
|
|
* dp? {number} Integer, -MAX_DP to MAX_DP inclusive.
|
|
* rm? 0, 1, 2 or 3 (ROUND_DOWN, ROUND_HALF_UP, ROUND_HALF_EVEN, ROUND_UP)
|
|
*/
|
|
P.round = function (dp, rm) {
|
|
var Big = this.constructor;
|
|
if (dp === UNDEFINED) dp = 0;
|
|
else if (dp !== ~~dp || dp < -MAX_DP || dp > MAX_DP) throw Error(INVALID_DP);
|
|
return round(new Big(this), dp, rm === UNDEFINED ? Big.RM : rm);
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a new Big whose value is the square root of the value of this Big, rounded, if
|
|
* necessary, to a maximum of Big.DP decimal places using rounding mode Big.RM.
|
|
*/
|
|
P.sqrt = function () {
|
|
var r, c, t,
|
|
x = this,
|
|
Big = x.constructor,
|
|
s = x.s,
|
|
e = x.e,
|
|
half = new Big(0.5);
|
|
|
|
// Zero?
|
|
if (!x.c[0]) return new Big(x);
|
|
|
|
// Negative?
|
|
if (s < 0) throw Error(NAME + 'No square root');
|
|
|
|
// Estimate.
|
|
s = Math.sqrt(x + '');
|
|
|
|
// Math.sqrt underflow/overflow?
|
|
// Re-estimate: pass x coefficient to Math.sqrt as integer, then adjust the result exponent.
|
|
if (s === 0 || s === 1 / 0) {
|
|
c = x.c.join('');
|
|
if (!(c.length + e & 1)) c += '0';
|
|
s = Math.sqrt(c);
|
|
e = ((e + 1) / 2 | 0) - (e < 0 || e & 1);
|
|
r = new Big((s == 1 / 0 ? '1e' : (s = s.toExponential()).slice(0, s.indexOf('e') + 1)) + e);
|
|
} else {
|
|
r = new Big(s);
|
|
}
|
|
|
|
e = r.e + (Big.DP += 4);
|
|
|
|
// Newton-Raphson iteration.
|
|
do {
|
|
t = r;
|
|
r = half.times(t.plus(x.div(t)));
|
|
} while (t.c.slice(0, e).join('') !== r.c.slice(0, e).join(''));
|
|
|
|
return round(r, Big.DP -= 4, Big.RM);
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a new Big whose value is the value of this Big times the value of Big y.
|
|
*/
|
|
P.times = P.mul = function (y) {
|
|
var c,
|
|
x = this,
|
|
Big = x.constructor,
|
|
xc = x.c,
|
|
yc = (y = new Big(y)).c,
|
|
a = xc.length,
|
|
b = yc.length,
|
|
i = x.e,
|
|
j = y.e;
|
|
|
|
// Determine sign of result.
|
|
y.s = x.s == y.s ? 1 : -1;
|
|
|
|
// Return signed 0 if either 0.
|
|
if (!xc[0] || !yc[0]) return new Big(y.s * 0);
|
|
|
|
// Initialise exponent of result as x.e + y.e.
|
|
y.e = i + j;
|
|
|
|
// If array xc has fewer digits than yc, swap xc and yc, and lengths.
|
|
if (a < b) {
|
|
c = xc;
|
|
xc = yc;
|
|
yc = c;
|
|
j = a;
|
|
a = b;
|
|
b = j;
|
|
}
|
|
|
|
// Initialise coefficient array of result with zeros.
|
|
for (c = new Array(j = a + b); j--;) c[j] = 0;
|
|
|
|
// Multiply.
|
|
|
|
// i is initially xc.length.
|
|
for (i = b; i--;) {
|
|
b = 0;
|
|
|
|
// a is yc.length.
|
|
for (j = a + i; j > i;) {
|
|
|
|
// Current sum of products at this digit position, plus carry.
|
|
b = c[j] + yc[i] * xc[j - i - 1] + b;
|
|
c[j--] = b % 10;
|
|
|
|
// carry
|
|
b = b / 10 | 0;
|
|
}
|
|
|
|
c[j] = (c[j] + b) % 10;
|
|
}
|
|
|
|
// Increment result exponent if there is a final carry, otherwise remove leading zero.
|
|
if (b) ++y.e;
|
|
else c.shift();
|
|
|
|
// Remove trailing zeros.
|
|
for (i = c.length; !c[--i];) c.pop();
|
|
y.c = c;
|
|
|
|
return y;
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a string representing the value of this Big in exponential notation to dp fixed decimal
|
|
* places and rounded using Big.RM.
|
|
*
|
|
* dp? {number} Integer, 0 to MAX_DP inclusive.
|
|
*/
|
|
P.toExponential = function (dp) {
|
|
return stringify(this, 1, dp, dp);
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a string representing the value of this Big in normal notation to dp fixed decimal
|
|
* places and rounded using Big.RM.
|
|
*
|
|
* dp? {number} Integer, 0 to MAX_DP inclusive.
|
|
*
|
|
* (-0).toFixed(0) is '0', but (-0.1).toFixed(0) is '-0'.
|
|
* (-0).toFixed(1) is '0.0', but (-0.01).toFixed(1) is '-0.0'.
|
|
*/
|
|
P.toFixed = function (dp) {
|
|
return stringify(this, 2, dp, this.e + dp);
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a string representing the value of this Big rounded to sd significant digits using
|
|
* Big.RM. Use exponential notation if sd is less than the number of digits necessary to represent
|
|
* the integer part of the value in normal notation.
|
|
*
|
|
* sd {number} Integer, 1 to MAX_DP inclusive.
|
|
*/
|
|
P.toPrecision = function (sd) {
|
|
return stringify(this, 3, sd, sd - 1);
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a string representing the value of this Big.
|
|
* Return exponential notation if this Big has a positive exponent equal to or greater than
|
|
* Big.PE, or a negative exponent equal to or less than Big.NE.
|
|
* Omit the sign for negative zero.
|
|
*/
|
|
P.toString = function () {
|
|
return stringify(this);
|
|
};
|
|
|
|
|
|
/*
|
|
* Return a string representing the value of this Big.
|
|
* Return exponential notation if this Big has a positive exponent equal to or greater than
|
|
* Big.PE, or a negative exponent equal to or less than Big.NE.
|
|
* Include the sign for negative zero.
|
|
*/
|
|
P.valueOf = P.toJSON = function () {
|
|
return stringify(this, 4);
|
|
};
|
|
|
|
|
|
// Export
|
|
|
|
|
|
export var Big = _Big_();
|
|
|
|
export default Big;
|