math: doc
R=r
DELTA=173 (74 added, 14 deleted, 85 changed)
OCL=25753
CL=25767
diff --git a/src/lib/math/log.go b/src/lib/math/log.go
index 8874216..b24175b 100644
--- a/src/lib/math/log.go
+++ b/src/lib/math/log.go
@@ -70,6 +70,13 @@
// compiler will convert from decimal to binary accurately enough
// to produce the hexadecimal values shown.
+// Log returns the natural logarithm of x.
+//
+// Special cases are:
+// Log(+Inf) = +Inf
+// Log(0) = -Inf
+// Log(x < 0) = NaN
+// Log(NaN) = NaN
func Log(x float64) float64 {
const (
Ln2Hi = 6.93147180369123816490e-01; /* 3fe62e42 fee00000 */
@@ -113,11 +120,12 @@
return k*Ln2Hi - ((hfsq-(s*(hfsq+R)+k*Ln2Lo)) - f);
}
-func Log10(arg float64) float64 {
- if arg <= 0 {
+// Log10 returns the decimal logarthm of x.
+// The special cases are the same as for Log.
+func Log10(x float64) float64 {
+ if x <= 0 {
return NaN();
}
- return Log(arg) * (1/Ln10);
+ return Log(x) * (1/Ln10);
}
-
