/** * @license Fraction.js v4.0.12 09/09/2015 * http://www.xarg.org/2014/03/rational-numbers-in-javascript/ * * Copyright (c) 2015, Robert Eisele (robert@xarg.org) * Dual licensed under the MIT or GPL Version 2 licenses. **/ /** * * This class offers the possibility to calculate fractions. * You can pass a fraction in different formats. Either as array, as double, as string or as an integer. * * Array/Object form * [ 0 => , 1 => ] * [ n => , d => ] * * Integer form * - Single integer value * * Double form * - Single double value * * String form * 123.456 - a simple double * 123/456 - a string fraction * 123.'456' - a double with repeating decimal places * 123.(456) - synonym * 123.45'6' - a double with repeating last place * 123.45(6) - synonym * * Example: * * var f = new Fraction("9.4'31'"); * f.mul([-4, 3]).div(4.9); * */ (function(root) { "use strict"; // Maximum search depth for cyclic rational numbers. 2000 should be more than enough. // Example: 1/7 = 0.(142857) has 6 repeating decimal places. // If MAX_CYCLE_LEN gets reduced, long cycles will not be detected and toString() only gets the first 10 digits var MAX_CYCLE_LEN = 2000; // Parsed data to avoid calling "new" all the time var P = { "s": 1, "n": 0, "d": 1 }; function createError(name) { function errorConstructor() { var temp = Error.apply(this, arguments); temp['name'] = this['name'] = name; this['stack'] = temp['stack']; this['message'] = temp['message']; } /** * Error constructor * * @constructor */ function IntermediateInheritor() { } IntermediateInheritor.prototype = Error.prototype; errorConstructor.prototype = new IntermediateInheritor(); return errorConstructor; } var DivisionByZero = Fraction['DivisionByZero'] = createError('DivisionByZero'); var InvalidParameter = Fraction['InvalidParameter'] = createError('InvalidParameter'); function assign(n, s) { if (isNaN(n = parseInt(n, 10))) { throwInvalidParam(); } return n * s; } function throwInvalidParam() { throw new InvalidParameter(); } var parse = function(p1, p2) { var n = 0, d = 1, s = 1; var v = 0, w = 0, x = 0, y = 1, z = 1; var A = 0, B = 1; var C = 1, D = 1; var N = 10000000; var M; if (p1 === undefined || p1 === null) { /* void */ } else if (p2 !== undefined) { n = p1; d = p2; s = n * d; } else switch (typeof p1) { case "object": { if ("d" in p1 && "n" in p1) { n = p1["n"]; d = p1["d"]; if ("s" in p1) n *= p1["s"]; } else if (0 in p1) { n = p1[0]; if (1 in p1) d = p1[1]; } else { throwInvalidParam(); } s = n * d; break; } case "number": { if (p1 < 0) { s = p1; p1 = -p1; } if (p1 % 1 === 0) { n = p1; } else if (p1 > 0) { // check for != 0, scale would become NaN (log(0)), which converges really slow if (p1 >= 1) { z = Math.pow(10, Math.floor(1 + Math.log(p1) / Math.LN10)); p1 /= z; } // Using Farey Sequences // http://www.johndcook.com/blog/2010/10/20/best-rational-approximation/ while (B <= N && D <= N) { M = (A + C) / (B + D); if (p1 === M) { if (B + D <= N) { n = A + C; d = B + D; } else if (D > B) { n = C; d = D; } else { n = A; d = B; } break; } else { if (p1 > M) { A += C; B += D; } else { C += A; D += B; } if (B > N) { n = C; d = D; } else { n = A; d = B; } } } n *= z; } else if (isNaN(p1) || isNaN(p2)) { d = n = NaN; } break; } case "string": { B = p1.match(/\d+|./g); if (B === null) throwInvalidParam(); if (B[A] === '-') {// Check for minus sign at the beginning s = -1; A++; } else if (B[A] === '+') {// Check for plus sign at the beginning A++; } if (B.length === A + 1) { // Check if it's just a simple number "1234" w = assign(B[A++], s); } else if (B[A + 1] === '.' || B[A] === '.') { // Check if it's a decimal number if (B[A] !== '.') { // Handle 0.5 and .5 v = assign(B[A++], s); } A++; // Check for decimal places if (A + 1 === B.length || B[A + 1] === '(' && B[A + 3] === ')' || B[A + 1] === "'" && B[A + 3] === "'") { w = assign(B[A], s); y = Math.pow(10, B[A].length); A++; } // Check for repeating places if (B[A] === '(' && B[A + 2] === ')' || B[A] === "'" && B[A + 2] === "'") { x = assign(B[A + 1], s); z = Math.pow(10, B[A + 1].length) - 1; A += 3; } } else if (B[A + 1] === '/' || B[A + 1] === ':') { // Check for a simple fraction "123/456" or "123:456" w = assign(B[A], s); y = assign(B[A + 2], 1); A += 3; } else if (B[A + 3] === '/' && B[A + 1] === ' ') { // Check for a complex fraction "123 1/2" v = assign(B[A], s); w = assign(B[A + 2], s); y = assign(B[A + 4], 1); A += 5; } if (B.length <= A) { // Check for more tokens on the stack d = y * z; s = /* void */ n = x + d * v + z * w; break; } /* Fall through on error */ } default: throwInvalidParam(); } if (d === 0) { throw new DivisionByZero(); } P["s"] = s < 0 ? -1 : 1; P["n"] = Math.abs(n); P["d"] = Math.abs(d); }; function modpow(b, e, m) { var r = 1; for (; e > 0; b = (b * b) % m, e >>= 1) { if (e & 1) { r = (r * b) % m; } } return r; } function cycleLen(n, d) { for (; d % 2 === 0; d /= 2) { } for (; d % 5 === 0; d /= 5) { } if (d === 1) // Catch non-cyclic numbers return 0; // If we would like to compute really large numbers quicker, we could make use of Fermat's little theorem: // 10^(d-1) % d == 1 // However, we don't need such large numbers and MAX_CYCLE_LEN should be the capstone, // as we want to translate the numbers to strings. var rem = 10 % d; var t = 1; for (; rem !== 1; t++) { rem = rem * 10 % d; if (t > MAX_CYCLE_LEN) return 0; // Returning 0 here means that we don't print it as a cyclic number. It's likely that the answer is `d-1` } return t; } function cycleStart(n, d, len) { var rem1 = 1; var rem2 = modpow(10, len, d); for (var t = 0; t < 300; t++) { // s < ~log10(Number.MAX_VALUE) // Solve 10^s == 10^(s+t) (mod d) if (rem1 === rem2) return t; rem1 = rem1 * 10 % d; rem2 = rem2 * 10 % d; } return 0; } function gcd(a, b) { if (!a) return b; if (!b) return a; while (1) { a %= b; if (!a) return b; b %= a; if (!b) return a; } }; /** * Module constructor * * @constructor * @param {number|Fraction=} a * @param {number=} b */ function Fraction(a, b) { if (!(this instanceof Fraction)) { return new Fraction(a, b); } parse(a, b); if (Fraction['REDUCE']) { a = gcd(P["d"], P["n"]); // Abuse a } else { a = 1; } this["s"] = P["s"]; this["n"] = P["n"] / a; this["d"] = P["d"] / a; } /** * Boolean global variable to be able to disable automatic reduction of the fraction * */ Fraction['REDUCE'] = 1; Fraction.prototype = { "s": 1, "n": 0, "d": 1, /** * Calculates the absolute value * * Ex: new Fraction(-4).abs() => 4 **/ "abs": function() { return new Fraction(this["n"], this["d"]); }, /** * Inverts the sign of the current fraction * * Ex: new Fraction(-4).neg() => 4 **/ "neg": function() { return new Fraction(-this["s"] * this["n"], this["d"]); }, /** * Adds two rational numbers * * Ex: new Fraction({n: 2, d: 3}).add("14.9") => 467 / 30 **/ "add": function(a, b) { parse(a, b); return new Fraction( this["s"] * this["n"] * P["d"] + P["s"] * this["d"] * P["n"], this["d"] * P["d"] ); }, /** * Subtracts two rational numbers * * Ex: new Fraction({n: 2, d: 3}).add("14.9") => -427 / 30 **/ "sub": function(a, b) { parse(a, b); return new Fraction( this["s"] * this["n"] * P["d"] - P["s"] * this["d"] * P["n"], this["d"] * P["d"] ); }, /** * Multiplies two rational numbers * * Ex: new Fraction("-17.(345)").mul(3) => 5776 / 111 **/ "mul": function(a, b) { parse(a, b); return new Fraction( this["s"] * P["s"] * this["n"] * P["n"], this["d"] * P["d"] ); }, /** * Divides two rational numbers * * Ex: new Fraction("-17.(345)").inverse().div(3) **/ "div": function(a, b) { parse(a, b); return new Fraction( this["s"] * P["s"] * this["n"] * P["d"], this["d"] * P["n"] ); }, /** * Clones the actual object * * Ex: new Fraction("-17.(345)").clone() **/ "clone": function() { return new Fraction(this); }, /** * Calculates the modulo of two rational numbers - a more precise fmod * * Ex: new Fraction('4.(3)').mod([7, 8]) => (13/3) % (7/8) = (5/6) **/ "mod": function(a, b) { if (isNaN(this['n']) || isNaN(this['d'])) { return new Fraction(NaN); } if (a === undefined) { return new Fraction(this["s"] * this["n"] % this["d"], 1); } parse(a, b); if (0 === P["n"] && 0 === this["d"]) { Fraction(0, 0); // Throw DivisionByZero } /* * First silly attempt, kinda slow * return that["sub"]({ "n": num["n"] * Math.floor((this.n / this.d) / (num.n / num.d)), "d": num["d"], "s": this["s"] });*/ /* * New attempt: a1 / b1 = a2 / b2 * q + r * => b2 * a1 = a2 * b1 * q + b1 * b2 * r * => (b2 * a1 % a2 * b1) / (b1 * b2) */ return new Fraction( this["s"] * (P["d"] * this["n"]) % (P["n"] * this["d"]), P["d"] * this["d"] ); }, /** * Calculates the fractional gcd of two rational numbers * * Ex: new Fraction(5,8).gcd(3,7) => 1/56 */ "gcd": function(a, b) { parse(a, b); // gcd(a / b, c / d) = gcd(a, c) / lcm(b, d) return new Fraction(gcd(P["n"], this["n"]) * gcd(P["d"], this["d"]), P["d"] * this["d"]); }, /** * Calculates the fractional lcm of two rational numbers * * Ex: new Fraction(5,8).lcm(3,7) => 15 */ "lcm": function(a, b) { parse(a, b); // lcm(a / b, c / d) = lcm(a, c) / gcd(b, d) if (P["n"] === 0 && this["n"] === 0) { return new Fraction; } return new Fraction(P["n"] * this["n"], gcd(P["n"], this["n"]) * gcd(P["d"], this["d"])); }, /** * Calculates the ceil of a rational number * * Ex: new Fraction('4.(3)').ceil() => (5 / 1) **/ "ceil": function(places) { places = Math.pow(10, places || 0); if (isNaN(this["n"]) || isNaN(this["d"])) { return new Fraction(NaN); } return new Fraction(Math.ceil(places * this["s"] * this["n"] / this["d"]), places); }, /** * Calculates the floor of a rational number * * Ex: new Fraction('4.(3)').floor() => (4 / 1) **/ "floor": function(places) { places = Math.pow(10, places || 0); if (isNaN(this["n"]) || isNaN(this["d"])) { return new Fraction(NaN); } return new Fraction(Math.floor(places * this["s"] * this["n"] / this["d"]), places); }, /** * Rounds a rational numbers * * Ex: new Fraction('4.(3)').round() => (4 / 1) **/ "round": function(places) { places = Math.pow(10, places || 0); if (isNaN(this["n"]) || isNaN(this["d"])) { return new Fraction(NaN); } return new Fraction(Math.round(places * this["s"] * this["n"] / this["d"]), places); }, /** * Gets the inverse of the fraction, means numerator and denominator are exchanged * * Ex: new Fraction([-3, 4]).inverse() => -4 / 3 **/ "inverse": function() { return new Fraction(this["s"] * this["d"], this["n"]); }, /** * Calculates the fraction to some integer exponent * * Ex: new Fraction(-1,2).pow(-3) => -8 */ "pow": function(m) { if (m < 0) { return new Fraction(Math.pow(this['s'] * this["d"], -m), Math.pow(this["n"], -m)); } else { return new Fraction(Math.pow(this['s'] * this["n"], m), Math.pow(this["d"], m)); } }, /** * Check if two rational numbers are the same * * Ex: new Fraction(19.6).equals([98, 5]); **/ "equals": function(a, b) { parse(a, b); return this["s"] * this["n"] * P["d"] === P["s"] * P["n"] * this["d"]; // Same as compare() === 0 }, /** * Check if two rational numbers are the same * * Ex: new Fraction(19.6).equals([98, 5]); **/ "compare": function(a, b) { parse(a, b); var t = (this["s"] * this["n"] * P["d"] - P["s"] * P["n"] * this["d"]); return (0 < t) - (t < 0); }, "simplify": function(eps) { // First naive implementation, needs improvement if (isNaN(this['n']) || isNaN(this['d'])) { return this; } var cont = this['abs']()['toContinued'](); eps = eps || 0.001; function rec(a) { if (a.length === 1) return new Fraction(a[0]); return rec(a.slice(1))['inverse']()['add'](a[0]); } for (var i = 0; i < cont.length; i++) { var tmp = rec(cont.slice(0, i + 1)); if (tmp['sub'](this['abs']())['abs']().valueOf() < eps) { return tmp['mul'](this['s']); } } return this; }, /** * Check if two rational numbers are divisible * * Ex: new Fraction(19.6).divisible(1.5); */ "divisible": function(a, b) { parse(a, b); return !(!(P["n"] * this["d"]) || ((this["n"] * P["d"]) % (P["n"] * this["d"]))); }, /** * Returns a decimal representation of the fraction * * Ex: new Fraction("100.'91823'").valueOf() => 100.91823918239183 **/ 'valueOf': function() { return this["s"] * this["n"] / this["d"]; }, /** * Returns a string-fraction representation of a Fraction object * * Ex: new Fraction("1.'3'").toFraction() => "4 1/3" **/ 'toFraction': function(excludeWhole) { var whole, str = ""; var n = this["n"]; var d = this["d"]; if (this["s"] < 0) { str += '-'; } if (d === 1) { str += n; } else { if (excludeWhole && (whole = Math.floor(n / d)) > 0) { str += whole; str += " "; n %= d; } str += n; str += '/'; str += d; } return str; }, /** * Returns a latex representation of a Fraction object * * Ex: new Fraction("1.'3'").toLatex() => "\frac{4}{3}" **/ 'toLatex': function(excludeWhole) { var whole, str = ""; var n = this["n"]; var d = this["d"]; if (this["s"] < 0) { str += '-'; } if (d === 1) { str += n; } else { if (excludeWhole && (whole = Math.floor(n / d)) > 0) { str += whole; n %= d; } str += "\\frac{"; str += n; str += '}{'; str += d; str += '}'; } return str; }, /** * Returns an array of continued fraction elements * * Ex: new Fraction("7/8").toContinued() => [0,1,7] */ 'toContinued': function() { var t; var a = this['n']; var b = this['d']; var res = []; if (isNaN(a) || isNaN(b)) { return res; } do { res.push(Math.floor(a / b)); t = a % b; a = b; b = t; } while (a !== 1); return res; }, /** * Creates a string representation of a fraction with all digits * * Ex: new Fraction("100.'91823'").toString() => "100.(91823)" **/ 'toString': function(dec) { var g; var N = this["n"]; var D = this["d"]; if (isNaN(N) || isNaN(D)) { return "NaN"; } if (!Fraction['REDUCE']) { g = gcd(N, D); N /= g; D /= g; } dec = dec || 15; // 15 = decimal places when no repitation var cycLen = cycleLen(N, D); // Cycle length var cycOff = cycleStart(N, D, cycLen); // Cycle start var str = this['s'] === -1 ? "-" : ""; str += N / D | 0; N %= D; N *= 10; if (N) str += "."; if (cycLen) { for (var i = cycOff; i--;) { str += N / D | 0; N %= D; N *= 10; } str += "("; for (var i = cycLen; i--;) { str += N / D | 0; N %= D; N *= 10; } str += ")"; } else { for (var i = dec; N && i--;) { str += N / D | 0; N %= D; N *= 10; } } return str; } }; if (typeof define === "function" && define["amd"]) { define([], function() { return Fraction; }); } else if (typeof exports === "object") { Object.defineProperty(Fraction, "__esModule", { 'value': true }); Fraction['default'] = Fraction; Fraction['Fraction'] = Fraction; module['exports'] = Fraction; } else { root['Fraction'] = Fraction; } })(this);