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- 'use strict';
- /**
- *
- * 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 => <numerator>, 1 => <denominator> ]
- * { n => <numerator>, d => <denominator> }
- *
- * Integer form
- * - Single integer value as BigInt or Number
- *
- * Double form
- * - Single double value as Number
- *
- * 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:
- * let f = new Fraction("9.4'31'");
- * f.mul([-4, 3]).div(4.9);
- *
- */
- // Set Identity function to downgrade BigInt to Number if needed
- if (typeof BigInt === 'undefined') BigInt = function (n) { if (isNaN(n)) throw new Error(""); return n; };
- const C_ZERO = BigInt(0);
- const C_ONE = BigInt(1);
- const C_TWO = BigInt(2);
- const C_THREE = BigInt(3);
- const C_FIVE = BigInt(5);
- const C_TEN = BigInt(10);
- const MAX_INTEGER = BigInt(Number.MAX_SAFE_INTEGER);
- // 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
- const MAX_CYCLE_LEN = 2000;
- // Parsed data to avoid calling "new" all the time
- const P = {
- "s": C_ONE,
- "n": C_ZERO,
- "d": C_ONE
- };
- function assign(n, s) {
- try {
- n = BigInt(n);
- } catch (e) {
- throw InvalidParameter();
- }
- return n * s;
- }
- function ifloor(x) {
- return typeof x === 'bigint' ? x : Math.floor(x);
- }
- // Creates a new Fraction internally without the need of the bulky constructor
- function newFraction(n, d) {
- if (d === C_ZERO) {
- throw DivisionByZero();
- }
- const f = Object.create(Fraction.prototype);
- f["s"] = n < C_ZERO ? -C_ONE : C_ONE;
- n = n < C_ZERO ? -n : n;
- const a = gcd(n, d);
- f["n"] = n / a;
- f["d"] = d / a;
- return f;
- }
- const FACTORSTEPS = [C_TWO * C_TWO, C_TWO, C_TWO * C_TWO, C_TWO, C_TWO * C_TWO, C_TWO * C_THREE, C_TWO, C_TWO * C_THREE]; // repeats
- function factorize(n) {
- const factors = Object.create(null);
- if (n <= C_ONE) {
- factors[n] = C_ONE;
- return factors;
- }
- const add = (p) => { factors[p] = (factors[p] || C_ZERO) + C_ONE; };
- while (n % C_TWO === C_ZERO) { add(C_TWO); n /= C_TWO; }
- while (n % C_THREE === C_ZERO) { add(C_THREE); n /= C_THREE; }
- while (n % C_FIVE === C_ZERO) { add(C_FIVE); n /= C_FIVE; }
- // 30-wheel trial division: test only residues coprime to 2*3*5
- // Residue step pattern after 5: 7,11,13,17,19,23,29,31, ...
- for (let si = 0, p = C_TWO + C_FIVE; p * p <= n;) {
- while (n % p === C_ZERO) { add(p); n /= p; }
- p += FACTORSTEPS[si];
- si = (si + 1) & 7; // fast modulo 8
- }
- if (n > C_ONE) add(n);
- return factors;
- }
- const parse = function (p1, p2) {
- let n = C_ZERO, d = C_ONE, s = C_ONE;
- if (p1 === undefined || p1 === null) { // No argument
- /* void */
- } else if (p2 !== undefined) { // Two arguments
- if (typeof p1 === "bigint") {
- n = p1;
- } else if (isNaN(p1)) {
- throw InvalidParameter();
- } else if (p1 % 1 !== 0) {
- throw NonIntegerParameter();
- } else {
- n = BigInt(p1);
- }
- if (typeof p2 === "bigint") {
- d = p2;
- } else if (isNaN(p2)) {
- throw InvalidParameter();
- } else if (p2 % 1 !== 0) {
- throw NonIntegerParameter();
- } else {
- d = BigInt(p2);
- }
- s = n * d;
- } else if (typeof p1 === "object") {
- if ("d" in p1 && "n" in p1) {
- n = BigInt(p1["n"]);
- d = BigInt(p1["d"]);
- if ("s" in p1)
- n *= BigInt(p1["s"]);
- } else if (0 in p1) {
- n = BigInt(p1[0]);
- if (1 in p1)
- d = BigInt(p1[1]);
- } else if (typeof p1 === "bigint") {
- n = p1;
- } else {
- throw InvalidParameter();
- }
- s = n * d;
- } else if (typeof p1 === "number") {
- if (isNaN(p1)) {
- throw InvalidParameter();
- }
- if (p1 < 0) {
- s = -C_ONE;
- p1 = -p1;
- }
- if (p1 % 1 === 0) {
- n = BigInt(p1);
- } else {
- let z = 1;
- let A = 0, B = 1;
- let C = 1, D = 1;
- let N = 10000000;
- if (p1 >= 1) {
- z = 10 ** Math.floor(1 + Math.log10(p1));
- p1 /= z;
- }
- // Using Farey Sequences
- while (B <= N && D <= N) {
- let 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 = BigInt(n) * BigInt(z);
- d = BigInt(d);
- }
- } else if (typeof p1 === "string") {
- let ndx = 0;
- let v = C_ZERO, w = C_ZERO, x = C_ZERO, y = C_ONE, z = C_ONE;
- let match = p1.replace(/_/g, '').match(/\d+|./g);
- if (match === null)
- throw InvalidParameter();
- if (match[ndx] === '-') {// Check for minus sign at the beginning
- s = -C_ONE;
- ndx++;
- } else if (match[ndx] === '+') {// Check for plus sign at the beginning
- ndx++;
- }
- if (match.length === ndx + 1) { // Check if it's just a simple number "1234"
- w = assign(match[ndx++], s);
- } else if (match[ndx + 1] === '.' || match[ndx] === '.') { // Check if it's a decimal number
- if (match[ndx] !== '.') { // Handle 0.5 and .5
- v = assign(match[ndx++], s);
- }
- ndx++;
- // Check for decimal places
- if (ndx + 1 === match.length || match[ndx + 1] === '(' && match[ndx + 3] === ')' || match[ndx + 1] === "'" && match[ndx + 3] === "'") {
- w = assign(match[ndx], s);
- y = C_TEN ** BigInt(match[ndx].length);
- ndx++;
- }
- // Check for repeating places
- if (match[ndx] === '(' && match[ndx + 2] === ')' || match[ndx] === "'" && match[ndx + 2] === "'") {
- x = assign(match[ndx + 1], s);
- z = C_TEN ** BigInt(match[ndx + 1].length) - C_ONE;
- ndx += 3;
- }
- } else if (match[ndx + 1] === '/' || match[ndx + 1] === ':') { // Check for a simple fraction "123/456" or "123:456"
- w = assign(match[ndx], s);
- y = assign(match[ndx + 2], C_ONE);
- ndx += 3;
- } else if (match[ndx + 3] === '/' && match[ndx + 1] === ' ') { // Check for a complex fraction "123 1/2"
- v = assign(match[ndx], s);
- w = assign(match[ndx + 2], s);
- y = assign(match[ndx + 4], C_ONE);
- ndx += 5;
- }
- if (match.length <= ndx) { // Check for more tokens on the stack
- d = y * z;
- s = /* void */
- n = x + d * v + z * w;
- } else {
- throw InvalidParameter();
- }
- } else if (typeof p1 === "bigint") {
- n = p1;
- s = p1;
- d = C_ONE;
- } else {
- throw InvalidParameter();
- }
- if (d === C_ZERO) {
- throw DivisionByZero();
- }
- P["s"] = s < C_ZERO ? -C_ONE : C_ONE;
- P["n"] = n < C_ZERO ? -n : n;
- P["d"] = d < C_ZERO ? -d : d;
- };
- function modpow(b, e, m) {
- let r = C_ONE;
- for (; e > C_ZERO; b = (b * b) % m, e >>= C_ONE) {
- if (e & C_ONE) {
- r = (r * b) % m;
- }
- }
- return r;
- }
- function cycleLen(n, d) {
- for (; d % C_TWO === C_ZERO;
- d /= C_TWO) {
- }
- for (; d % C_FIVE === C_ZERO;
- d /= C_FIVE) {
- }
- if (d === C_ONE) // Catch non-cyclic numbers
- return C_ZERO;
- // 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.
- let rem = C_TEN % d;
- let t = 1;
- for (; rem !== C_ONE; t++) {
- rem = rem * C_TEN % d;
- if (t > MAX_CYCLE_LEN)
- return C_ZERO; // Returning 0 here means that we don't print it as a cyclic number. It's likely that the answer is `d-1`
- }
- return BigInt(t);
- }
- function cycleStart(n, d, len) {
- let rem1 = C_ONE;
- let rem2 = modpow(C_TEN, len, d);
- for (let t = 0; t < 300; t++) { // s < ~log10(Number.MAX_VALUE)
- // Solve 10^s == 10^(s+t) (mod d)
- if (rem1 === rem2)
- return BigInt(t);
- rem1 = rem1 * C_TEN % d;
- rem2 = rem2 * C_TEN % 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) {
- parse(a, b);
- if (this instanceof Fraction) {
- a = gcd(P["d"], P["n"]); // Abuse a
- this["s"] = P["s"];
- this["n"] = P["n"] / a;
- this["d"] = P["d"] / a;
- } else {
- return newFraction(P['s'] * P['n'], P['d']);
- }
- }
- const DivisionByZero = function () { return new Error("Division by Zero"); };
- const InvalidParameter = function () { return new Error("Invalid argument"); };
- const NonIntegerParameter = function () { return new Error("Parameters must be integer"); };
- Fraction.prototype = {
- "s": C_ONE,
- "n": C_ZERO,
- "d": C_ONE,
- /**
- * Calculates the absolute value
- *
- * Ex: new Fraction(-4).abs() => 4
- **/
- "abs": function () {
- return newFraction(this["n"], this["d"]);
- },
- /**
- * Inverts the sign of the current fraction
- *
- * Ex: new Fraction(-4).neg() => 4
- **/
- "neg": function () {
- return newFraction(-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 newFraction(
- 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 newFraction(
- 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 newFraction(
- 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 newFraction(
- 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 newFraction(this['s'] * this['n'], this['d']);
- },
- /**
- * 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)
- * Ex: new Fraction(20, 10).mod().equals(0) ? "is Integer"
- **/
- "mod": function (a, b) {
- if (a === undefined) {
- return newFraction(this["s"] * this["n"] % this["d"], C_ONE);
- }
- parse(a, b);
- if (C_ZERO === P["n"] * this["d"]) {
- throw DivisionByZero();
- }
- /**
- * I derived the rational modulo similar to the modulo for integers
- *
- * https://raw.org/book/analysis/rational-numbers/
- *
- * n1/d1 = (n2/d2) * q + r, where 0 ≤ r < n2/d2
- * => d2 * n1 = n2 * d1 * q + d1 * d2 * r
- * => r = (d2 * n1 - n2 * d1 * q) / (d1 * d2)
- * = (d2 * n1 - n2 * d1 * floor((d2 * n1) / (n2 * d1))) / (d1 * d2)
- * = ((d2 * n1) % (n2 * d1)) / (d1 * d2)
- */
- return newFraction(
- 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);
- // https://raw.org/book/analysis/rational-numbers/
- // gcd(a / b, c / d) = gcd(a, c) / lcm(b, d)
- return newFraction(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);
- // https://raw.org/book/analysis/rational-numbers/
- // lcm(a / b, c / d) = lcm(a, c) / gcd(b, d)
- if (P["n"] === C_ZERO && this["n"] === C_ZERO) {
- return newFraction(C_ZERO, C_ONE);
- }
- return newFraction(P["n"] * this["n"], gcd(P["n"], this["n"]) * gcd(P["d"], this["d"]));
- },
- /**
- * Gets the inverse of the fraction, means numerator and denominator are exchanged
- *
- * Ex: new Fraction([-3, 4]).inverse() => -4 / 3
- **/
- "inverse": function () {
- return newFraction(this["s"] * this["d"], this["n"]);
- },
- /**
- * Calculates the fraction to some integer exponent
- *
- * Ex: new Fraction(-1,2).pow(-3) => -8
- */
- "pow": function (a, b) {
- parse(a, b);
- // Trivial case when exp is an integer
- if (P['d'] === C_ONE) {
- if (P['s'] < C_ZERO) {
- return newFraction((this['s'] * this["d"]) ** P['n'], this["n"] ** P['n']);
- } else {
- return newFraction((this['s'] * this["n"]) ** P['n'], this["d"] ** P['n']);
- }
- }
- // Negative roots become complex
- // (-a/b)^(c/d) = x
- // ⇔ (-1)^(c/d) * (a/b)^(c/d) = x
- // ⇔ (cos(pi) + i*sin(pi))^(c/d) * (a/b)^(c/d) = x
- // ⇔ (cos(c*pi/d) + i*sin(c*pi/d)) * (a/b)^(c/d) = x # DeMoivre's formula
- // From which follows that only for c=0 the root is non-complex
- if (this['s'] < C_ZERO) return null;
- // Now prime factor n and d
- let N = factorize(this['n']);
- let D = factorize(this['d']);
- // Exponentiate and take root for n and d individually
- let n = C_ONE;
- let d = C_ONE;
- for (let k in N) {
- if (k === '1') continue;
- if (k === '0') {
- n = C_ZERO;
- break;
- }
- N[k] *= P['n'];
- if (N[k] % P['d'] === C_ZERO) {
- N[k] /= P['d'];
- } else return null;
- n *= BigInt(k) ** N[k];
- }
- for (let k in D) {
- if (k === '1') continue;
- D[k] *= P['n'];
- if (D[k] % P['d'] === C_ZERO) {
- D[k] /= P['d'];
- } else return null;
- d *= BigInt(k) ** D[k];
- }
- if (P['s'] < C_ZERO) {
- return newFraction(d, n);
- }
- return newFraction(n, d);
- },
- /**
- * Calculates the logarithm of a fraction to a given rational base
- *
- * Ex: new Fraction(27, 8).log(9, 4) => 3/2
- */
- "log": function (a, b) {
- parse(a, b);
- if (this['s'] <= C_ZERO || P['s'] <= C_ZERO) return null;
- const allPrimes = Object.create(null);
- const baseFactors = factorize(P['n']);
- const T1 = factorize(P['d']);
- const numberFactors = factorize(this['n']);
- const T2 = factorize(this['d']);
- for (const prime in T1) {
- baseFactors[prime] = (baseFactors[prime] || C_ZERO) - T1[prime];
- }
- for (const prime in T2) {
- numberFactors[prime] = (numberFactors[prime] || C_ZERO) - T2[prime];
- }
- for (const prime in baseFactors) {
- if (prime === '1') continue;
- allPrimes[prime] = true;
- }
- for (const prime in numberFactors) {
- if (prime === '1') continue;
- allPrimes[prime] = true;
- }
- let retN = null;
- let retD = null;
- // Iterate over all unique primes to determine if a consistent ratio exists
- for (const prime in allPrimes) {
- const baseExponent = baseFactors[prime] || C_ZERO;
- const numberExponent = numberFactors[prime] || C_ZERO;
- if (baseExponent === C_ZERO) {
- if (numberExponent !== C_ZERO) {
- return null; // Logarithm cannot be expressed as a rational number
- }
- continue; // Skip this prime since both exponents are zero
- }
- // Calculate the ratio of exponents for this prime
- let curN = numberExponent;
- let curD = baseExponent;
- // Simplify the current ratio
- const gcdValue = gcd(curN, curD);
- curN /= gcdValue;
- curD /= gcdValue;
- // Check if this is the first ratio; otherwise, ensure ratios are consistent
- if (retN === null && retD === null) {
- retN = curN;
- retD = curD;
- } else if (curN * retD !== retN * curD) {
- return null; // Ratios do not match, logarithm cannot be rational
- }
- }
- return retN !== null && retD !== null
- ? newFraction(retN, retD)
- : null;
- },
- /**
- * 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"];
- },
- /**
- * Check if this rational number is less than another
- *
- * Ex: new Fraction(19.6).lt([98, 5]);
- **/
- "lt": function (a, b) {
- parse(a, b);
- return this["s"] * this["n"] * P["d"] < P["s"] * P["n"] * this["d"];
- },
- /**
- * Check if this rational number is less than or equal another
- *
- * Ex: new Fraction(19.6).lt([98, 5]);
- **/
- "lte": function (a, b) {
- parse(a, b);
- return this["s"] * this["n"] * P["d"] <= P["s"] * P["n"] * this["d"];
- },
- /**
- * Check if this rational number is greater than another
- *
- * Ex: new Fraction(19.6).lt([98, 5]);
- **/
- "gt": function (a, b) {
- parse(a, b);
- return this["s"] * this["n"] * P["d"] > P["s"] * P["n"] * this["d"];
- },
- /**
- * Check if this rational number is greater than or equal another
- *
- * Ex: new Fraction(19.6).lt([98, 5]);
- **/
- "gte": function (a, b) {
- parse(a, b);
- return this["s"] * this["n"] * P["d"] >= P["s"] * P["n"] * this["d"];
- },
- /**
- * Compare two rational numbers
- * < 0 iff this < that
- * > 0 iff this > that
- * = 0 iff this = that
- *
- * Ex: new Fraction(19.6).compare([98, 5]);
- **/
- "compare": function (a, b) {
- parse(a, b);
- let t = this["s"] * this["n"] * P["d"] - P["s"] * P["n"] * this["d"];
- return (C_ZERO < t) - (t < C_ZERO);
- },
- /**
- * Calculates the ceil of a rational number
- *
- * Ex: new Fraction('4.(3)').ceil() => (5 / 1)
- **/
- "ceil": function (places) {
- places = C_TEN ** BigInt(places || 0);
- return newFraction(ifloor(this["s"] * places * this["n"] / this["d"]) +
- (places * this["n"] % this["d"] > C_ZERO && this["s"] >= C_ZERO ? C_ONE : C_ZERO),
- places);
- },
- /**
- * Calculates the floor of a rational number
- *
- * Ex: new Fraction('4.(3)').floor() => (4 / 1)
- **/
- "floor": function (places) {
- places = C_TEN ** BigInt(places || 0);
- return newFraction(ifloor(this["s"] * places * this["n"] / this["d"]) -
- (places * this["n"] % this["d"] > C_ZERO && this["s"] < C_ZERO ? C_ONE : C_ZERO),
- places);
- },
- /**
- * Rounds a rational numbers
- *
- * Ex: new Fraction('4.(3)').round() => (4 / 1)
- **/
- "round": function (places) {
- places = C_TEN ** BigInt(places || 0);
- /* Derivation:
- s >= 0:
- round(n / d) = ifloor(n / d) + (n % d) / d >= 0.5 ? 1 : 0
- = ifloor(n / d) + 2(n % d) >= d ? 1 : 0
- s < 0:
- round(n / d) =-ifloor(n / d) - (n % d) / d > 0.5 ? 1 : 0
- =-ifloor(n / d) - 2(n % d) > d ? 1 : 0
- =>:
- round(s * n / d) = s * ifloor(n / d) + s * (C + 2(n % d) > d ? 1 : 0)
- where C = s >= 0 ? 1 : 0, to fix the >= for the positve case.
- */
- return newFraction(ifloor(this["s"] * places * this["n"] / this["d"]) +
- this["s"] * ((this["s"] >= C_ZERO ? C_ONE : C_ZERO) + C_TWO * (places * this["n"] % this["d"]) > this["d"] ? C_ONE : C_ZERO),
- places);
- },
- /**
- * Rounds a rational number to a multiple of another rational number
- *
- * Ex: new Fraction('0.9').roundTo("1/8") => 7 / 8
- **/
- "roundTo": function (a, b) {
- /*
- k * x/y ≤ a/b < (k+1) * x/y
- ⇔ k ≤ a/b / (x/y) < (k+1)
- ⇔ k = floor(a/b * y/x)
- ⇔ k = floor((a * y) / (b * x))
- */
- parse(a, b);
- const n = this['n'] * P['d'];
- const d = this['d'] * P['n'];
- const r = n % d;
- // round(n / d) = ifloor(n / d) + 2(n % d) >= d ? 1 : 0
- let k = ifloor(n / d);
- if (r + r >= d) {
- k++;
- }
- return newFraction(this['s'] * k * P['n'], P['d']);
- },
- /**
- * Check if two rational numbers are divisible
- *
- * Ex: new Fraction(19.6).divisible(1.5);
- */
- "divisible": function (a, b) {
- parse(a, b);
- if (P['n'] === C_ZERO) return false;
- return (this['n'] * P['d']) % (P['n'] * this['d']) === C_ZERO;
- },
- /**
- * Returns a decimal representation of the fraction
- *
- * Ex: new Fraction("100.'91823'").valueOf() => 100.91823918239183
- **/
- 'valueOf': function () {
- //if (this['n'] <= MAX_INTEGER && this['d'] <= MAX_INTEGER) {
- return Number(this['s'] * this['n']) / Number(this['d']);
- //}
- },
- /**
- * Creates a string representation of a fraction with all digits
- *
- * Ex: new Fraction("100.'91823'").toString() => "100.(91823)"
- **/
- 'toString': function (dec = 15) {
- let N = this["n"];
- let D = this["d"];
- let cycLen = cycleLen(N, D); // Cycle length
- let cycOff = cycleStart(N, D, cycLen); // Cycle start
- let str = this['s'] < C_ZERO ? "-" : "";
- // Append integer part
- str += ifloor(N / D);
- N %= D;
- N *= C_TEN;
- if (N)
- str += ".";
- if (cycLen) {
- for (let i = cycOff; i--;) {
- str += ifloor(N / D);
- N %= D;
- N *= C_TEN;
- }
- str += "(";
- for (let i = cycLen; i--;) {
- str += ifloor(N / D);
- N %= D;
- N *= C_TEN;
- }
- str += ")";
- } else {
- for (let i = dec; N && i--;) {
- str += ifloor(N / D);
- N %= D;
- N *= C_TEN;
- }
- }
- return str;
- },
- /**
- * Returns a string-fraction representation of a Fraction object
- *
- * Ex: new Fraction("1.'3'").toFraction() => "4 1/3"
- **/
- 'toFraction': function (showMixed = false) {
- let n = this["n"];
- let d = this["d"];
- let str = this['s'] < C_ZERO ? "-" : "";
- if (d === C_ONE) {
- str += n;
- } else {
- const whole = ifloor(n / d);
- if (showMixed && whole > C_ZERO) {
- 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 (showMixed = false) {
- let n = this["n"];
- let d = this["d"];
- let str = this['s'] < C_ZERO ? "-" : "";
- if (d === C_ONE) {
- str += n;
- } else {
- const whole = ifloor(n / d);
- if (showMixed && whole > C_ZERO) {
- 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 () {
- let a = this['n'];
- let b = this['d'];
- const res = [];
- while (b) {
- res.push(ifloor(a / b));
- const t = a % b;
- a = b;
- b = t;
- }
- return res;
- },
- "simplify": function (eps = 1e-3) {
- // Continued fractions give best approximations for a max denominator,
- // generally outperforming mediants in denominator–accuracy trade-offs.
- // Semiconvergents can further reduce the denominator within tolerance.
- const ieps = BigInt(Math.ceil(1 / eps));
- const thisABS = this['abs']();
- const cont = thisABS['toContinued']();
- for (let i = 1; i < cont.length; i++) {
- let s = newFraction(cont[i - 1], C_ONE);
- for (let k = i - 2; k >= 0; k--) {
- s = s['inverse']()['add'](cont[k]);
- }
- let t = s['sub'](thisABS);
- if (t['n'] * ieps < t['d']) { // More robust than Math.abs(t.valueOf()) < eps
- return s['mul'](this['s']);
- }
- }
- return this;
- }
- };
- export {
- Fraction as default, Fraction
- };
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