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authorRuss Cox <rsc@golang.org>2008-11-19 16:14:31 -0800
committerRuss Cox <rsc@golang.org>2008-11-19 16:14:31 -0800
commit10893da6fd157d333222ba7ba38bd1865738bb68 (patch)
treef4567a04ec09e92c8896c1244eecad4f67eaa3d7 /src/lib/math/atan.go
parent07c8f5ddfebb4e38c039412df828ad65becf95b3 (diff)
downloadgolang-10893da6fd157d333222ba7ba38bd1865738bb68.tar.gz
gotestify & gostylify math.
R=r DELTA=682 (275 added, 301 deleted, 106 changed) OCL=19638 CL=19642
Diffstat (limited to 'src/lib/math/atan.go')
-rw-r--r--src/lib/math/atan.go31
1 files changed, 10 insertions, 21 deletions
diff --git a/src/lib/math/atan.go b/src/lib/math/atan.go
index aa4c29234..43990fe40 100644
--- a/src/lib/math/atan.go
+++ b/src/lib/math/atan.go
@@ -13,7 +13,6 @@ package math
* coefficients are #5077 from Hart & Cheney. (19.56D)
*/
-
const
(
p4 = .161536412982230228262e2;
@@ -36,13 +35,9 @@ const
* xatan evaluates a series valid in the
* range [-0.414...,+0.414...]. (tan(pi/8))
*/
-func
-xatan(arg float64) float64
-{
- var argsq, value float64;
-
- argsq = arg*arg;
- value = ((((p4*argsq + p3)*argsq + p2)*argsq + p1)*argsq + p0);
+func Xatan(arg float64) float64 {
+ argsq := arg*arg;
+ value := ((((p4*argsq + p3)*argsq + p2)*argsq + p1)*argsq + p0);
value = value/(((((argsq + q4)*argsq + q3)*argsq + q2)*argsq + q1)*argsq + q0);
return value*arg;
}
@@ -51,29 +46,23 @@ xatan(arg float64) float64
* satan reduces its argument (known to be positive)
* to the range [0,0.414...] and calls xatan.
*/
-func
-satan(arg float64) float64
-{
-
+func Satan(arg float64) float64 {
if arg < sq2m1 {
- return xatan(arg);
+ return Xatan(arg);
}
if arg > sq2p1 {
- return pio2 - xatan(1/arg);
+ return pio2 - Xatan(1/arg);
}
- return pio4 + xatan((arg-1)/(arg+1));
+ return pio4 + Xatan((arg-1)/(arg+1));
}
/*
* atan makes its argument positive and
* calls the inner routine satan.
*/
-export func
-atan(arg float64) float64
-{
-
+export func Atan(arg float64) float64 {
if arg > 0 {
- return satan(arg);
+ return Satan(arg);
}
- return -satan(-arg);
+ return -Satan(-arg);
}