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/**
*
* 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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