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3 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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22 * Contributor(s): Brendan Eich
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38 //-----------------------------------------------------------------------------
39 var BUGNUMBER = 363040;
40 var summary = 'Array.prototype.reduce application in continued fraction';
45 //-----------------------------------------------------------------------------
47 //-----------------------------------------------------------------------------
52 printBugNumber(BUGNUMBER);
53 printStatus (summary);
56 // Print x as a continued fraction in compact abbreviated notation and return
57 // the convergent [n, d] such that x - (n / d) <= epsilon.
58 function contfrac(x, epsilon) {
59 let i = Math.floor(x);
63 while (maxerr > epsilon) {
68 maxerr = x * maxerr / i;
71 return a.reduceRight(function (x, y) {return [x[0] * y + x[1], x[0]];}, [1, 0]);
74 if (!Array.prototype.reduceRight)
76 print('Test skipped. Array.prototype.reduceRight not implemented');
80 // Show contfrac in action on some interesting numbers.
81 for each (num in [Math.PI, Math.sqrt(2), 1 / (Math.sqrt(Math.E) - 1)]) {
82 print('Continued fractions for', num);
83 for each (eps in [1e-2, 1e-3, 1e-5, 1e-7, 1e-10]) {
84 let frac = contfrac(num, eps);
85 let est = frac[0] / frac[1];
87 print(uneval(frac), est, err);
93 reportCompare(expect, actual, summary);