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1f8a40d85c
though they still build in src/runtime. use cgo instead of hand-written wrappers. R=r DELTA=740 (289 added, 300 deleted, 151 changed) OCL=23326 CL=23331
48 lines
773 B
Go
48 lines
773 B
Go
// 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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import "math"
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/*
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* asin(arg) and acos(arg) return the arcsin, arccos,
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* respectively of their arguments.
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*
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* Arctan is called after appropriate range reduction.
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*/
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func Asin(arg float64) float64 {
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var temp, x float64;
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var sign bool;
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sign = false;
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x = arg;
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if x < 0 {
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x = -x;
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sign = true;
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}
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if arg > 1 {
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return NaN();
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}
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temp = Sqrt(1 - x*x);
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if x > 0.7 {
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temp = Pi/2 - Atan(temp/x);
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} else {
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temp = Atan(x/temp);
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}
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if sign {
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temp = -temp;
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}
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return temp;
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}
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func Acos(arg float64) float64 {
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if arg > 1 || arg < -1 {
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return NaN();
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}
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return Pi/2 - Asin(arg);
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}
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