54 lines
1.1 KiB
JavaScript
54 lines
1.1 KiB
JavaScript
/**
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* @license Fraction.js v2.7.0 01/06/2015
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* http://www.xarg.org/2014/03/rational-numbers-in-javascript/
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*
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* Copyright (c) 2015, Robert Eisele (robert@xarg.org)
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* Dual licensed under the MIT or GPL Version 2 licenses.
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**/
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// Another rational approximation, not using Farey Sequences but Binary Search using the mediant
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function approximate(p, precision) {
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var num1 = Math.floor(p);
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var den1 = 1;
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var num2 = num1 + 1;
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var den2 = 1;
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if (p !== num1) {
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while (den1 <= precision && den2 <= precision) {
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var m = (num1 + num2) / (den1 + den2);
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if (p === m) {
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if (den1 + den2 <= precision) {
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den1 += den2;
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num1 += num2;
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den2 = precision + 1;
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} else if (den1 > den2) {
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den2 = precision + 1;
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} else {
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den1 = precision + 1;
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}
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break;
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} else if (p < m) {
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num2 += num1;
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den2 += den1;
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} else {
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num1 += num2;
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den1 += den2;
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}
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}
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}
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if (den1 > precision) {
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den1 = den2;
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num1 = num2;
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}
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return new Fraction(num1, den1);
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}
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