diff options
Diffstat (limited to 'src/pkg/math/log1p.go')
| -rw-r--r-- | src/pkg/math/log1p.go | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/src/pkg/math/log1p.go b/src/pkg/math/log1p.go index c25d73b66..12b98684c 100644 --- a/src/pkg/math/log1p.go +++ b/src/pkg/math/log1p.go @@ -44,7 +44,7 @@ package math // 2 4 6 8 10 12 14 // R(z) ~ Lp1*s +Lp2*s +Lp3*s +Lp4*s +Lp5*s +Lp6*s +Lp7*s // (the values of Lp1 to Lp7 are listed in the program) -// a-0.2929nd +// and // | 2 14 | -58.45 // | Lp1*s +...+Lp7*s - R(z) | <= 2 // | | @@ -88,10 +88,13 @@ package math // // Special cases are: // Log1p(+Inf) = +Inf +// Log1p(±0) = ±0 // Log1p(-1) = -Inf // Log1p(x < -1) = NaN // Log1p(NaN) = NaN -func Log1p(x float64) float64 { +func Log1p(x float64) float64 + +func log1p(x float64) float64 { const ( Sqrt2M1 = 4.142135623730950488017e-01 // Sqrt(2)-1 = 0x3fda827999fcef34 Sqrt2HalfM1 = -2.928932188134524755992e-01 // Sqrt(2)/2-1 = 0xbfd2bec333018866 @@ -110,14 +113,12 @@ func Log1p(x float64) float64 { ) // special cases - // TODO(rsc): Remove manual inlining of IsNaN, IsInf - // when compiler does it for us switch { - case x < -1 || x != x: // x < -1 || IsNaN(x): // includes -Inf + case x < -1 || IsNaN(x): // includes -Inf return NaN() case x == -1: return Inf(-1) - case x > MaxFloat64: // IsInf(x, 1): + case IsInf(x, 1): return Inf(1) } |