2010-12-03 05:34:57 +01:00
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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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package math
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2011-10-27 01:57:58 +02:00
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// Abs returns the absolute value of x.
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2010-12-03 05:34:57 +01:00
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//
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// Special cases are:
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2011-12-13 20:16:27 +01:00
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// Abs(±Inf) = +Inf
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2011-10-27 01:57:58 +02:00
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// Abs(NaN) = NaN
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2012-02-07 20:26:30 +01:00
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//extern fabs
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func libc_fabs(float64) float64
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2011-10-27 01:57:58 +02:00
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func Abs(x float64) float64 {
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2012-01-12 02:31:45 +01:00
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return libc_fabs(x)
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}
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func abs(x float64) float64 {
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2010-12-03 05:34:57 +01:00
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switch {
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case x < 0:
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return -x
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case x == 0:
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2011-10-27 01:57:58 +02:00
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return 0 // return correctly abs(-0)
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2010-12-03 05:34:57 +01:00
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}
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return x
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}
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