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gotestify & gostylify math.

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R=r
DELTA=682  (275 added, 301 deleted, 106 changed)
OCL=19638
CL=19642
This commit is contained in:
Russ Cox 2008-11-19 16:14:31 -08:00
parent be7e0f8160
commit 88daac7862
18 changed files with 385 additions and 411 deletions
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26
src/lib/math/log.go
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@ -5,7 +5,7 @@
package math
/*
* log returns the natural logarithm of its floating
* Log returns the natural logarithm of its floating
* point argument.
*
* The coefficients are #2705 from Hart & Cheney. (19.38D)
@ -16,7 +16,7 @@ package math
const
(
log2 = .693147180559945309e0;
ln10o1 = .4342944819032518276511;
ln10u1 = .4342944819032518276511;
sqrto2 = .707106781186547524e0;
p0 = -.240139179559210510e2;
p1 = .309572928215376501e2;
@ -27,17 +27,12 @@ const
q2 = -.891110902798312337e1;
)
export func
log(arg float64) float64
{
var x, z, zsq, temp float64;
var exp int;
export func Log(arg float64) float64 {
if arg <= 0 {
return sys.NaN();
}
x,exp = sys.frexp(arg);
x, exp := sys.frexp(arg);
for x < 0.5 {
x = x*2;
exp = exp-1;
@ -47,21 +42,18 @@ log(arg float64) float64
exp = exp-1;
}
z = (x-1) / (x+1);
zsq = z*z;
z := (x-1) / (x+1);
zsq := z*z;
temp = ((p3*zsq + p2)*zsq + p1)*zsq + p0;
temp := ((p3*zsq + p2)*zsq + p1)*zsq + p0;
temp = temp/(((zsq + q2)*zsq + q1)*zsq + q0);
temp = temp*z + float64(exp)*log2;
return temp;
}
export func
log10(arg float64) float64
{
export func Log10(arg float64) float64 {
if arg <= 0 {
return sys.NaN();
}
return log(arg) * ln10o1;
return Log(arg) * ln10u1;
}