2008-03-28 14:56:47 -06:00
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// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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2008-06-27 18:06:23 -06:00
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package math
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2008-03-28 14:56:47 -06:00
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2009-01-22 17:23:44 -07:00
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2008-03-28 14:56:47 -06:00
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/*
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2008-07-08 21:48:41 -06:00
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* floating-point mod func without infinity or NaN checking
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2008-03-28 14:56:47 -06:00
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*/
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2009-03-05 14:31:01 -07:00
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// Fmod returns the floating-point remainder of x/y.
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2009-01-20 15:40:40 -07:00
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func Fmod(x, y float64) float64 {
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if y == 0 {
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2009-11-09 13:07:39 -07:00
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return x
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2008-03-28 14:56:47 -06:00
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}
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if y < 0 {
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2009-11-09 13:07:39 -07:00
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y = -y
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2008-03-28 14:56:47 -06:00
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}
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2009-01-22 17:23:44 -07:00
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yfr, yexp := Frexp(y);
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2008-11-19 17:14:31 -07:00
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sign := false;
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r := x;
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2008-03-28 14:56:47 -06:00
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if x < 0 {
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r = -x;
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sign = true;
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}
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for r >= y {
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2009-01-22 17:23:44 -07:00
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rfr, rexp := Frexp(r);
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2008-03-28 14:56:47 -06:00
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if rfr < yfr {
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2009-11-09 13:07:39 -07:00
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rexp = rexp-1
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2008-03-28 14:56:47 -06:00
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}
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2009-01-22 17:23:44 -07:00
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r = r - Ldexp(y, rexp-yexp);
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2008-03-28 14:56:47 -06:00
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}
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if sign {
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2009-11-09 13:07:39 -07:00
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r = -r
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2008-03-28 14:56:47 -06:00
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}
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return r;
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}
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