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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export fmod
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/*
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floating-point mod func without infinity or NaN checking
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*/
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func
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fmod(x, y double) double
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{
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var yexp, rexp int;
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var r, yfr, rfr double;
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var sign bool;
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if y == 0 {
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return x;
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}
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if y < 0 {
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y = -y;
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}
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2008-07-08 18:26:10 -06:00
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yfr,yexp = sys.frexp(y);
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2008-03-28 14:56:47 -06:00
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sign = false;
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if x < 0 {
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r = -x;
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sign = true;
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} else {
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r = x;
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}
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for r >= y {
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2008-07-08 18:26:10 -06:00
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rfr,rexp = sys.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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rexp = rexp - 1;
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}
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2008-07-08 18:26:10 -06:00
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r = r - sys.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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r = -r;
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}
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return r;
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}
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