jiangchengfeiyi-xiaochengxu/node_modules/fraction.js/examples/approx.js
2025-04-02 23:45:33 +08:00

55 lines
1.1 KiB
JavaScript

/*
Fraction.js v5.0.0 10/1/2024
https://raw.org/article/rational-numbers-in-javascript/
Copyright (c) 2024, Robert Eisele (https://raw.org/)
Licensed under the MIT license.
*/
const Fraction = require('fraction.js');
// Another rational approximation, not using Farey Sequences but Binary Search using the mediant
function approximate(p, precision) {
var num1 = Math.floor(p);
var den1 = 1;
var num2 = num1 + 1;
var den2 = 1;
if (p !== num1) {
while (den1 <= precision && den2 <= precision) {
var m = (num1 + num2) / (den1 + den2);
if (p === m) {
if (den1 + den2 <= precision) {
den1 += den2;
num1 += num2;
den2 = precision + 1;
} else if (den1 > den2) {
den2 = precision + 1;
} else {
den1 = precision + 1;
}
break;
} else if (p < m) {
num2 += num1;
den2 += den1;
} else {
num1 += num2;
den1 += den2;
}
}
}
if (den1 > precision) {
den1 = den2;
num1 = num2;
}
return new Fraction(num1, den1);
}