diff options
Diffstat (limited to 'src/pkg/math/ldexp.go')
-rw-r--r-- | src/pkg/math/ldexp.go | 45 |
1 files changed, 0 insertions, 45 deletions
diff --git a/src/pkg/math/ldexp.go b/src/pkg/math/ldexp.go deleted file mode 100644 index b5d2a5e7e..000000000 --- a/src/pkg/math/ldexp.go +++ /dev/null @@ -1,45 +0,0 @@ -// Copyright 2009 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -package math - -// Ldexp is the inverse of Frexp. -// It returns frac × 2**exp. -// -// Special cases are: -// Ldexp(±0, exp) = ±0 -// Ldexp(±Inf, exp) = ±Inf -// Ldexp(NaN, exp) = NaN -func Ldexp(frac float64, exp int) float64 - -func ldexp(frac float64, exp int) float64 { - // special cases - switch { - case frac == 0: - return frac // correctly return -0 - case IsInf(frac, 0) || IsNaN(frac): - return frac - } - frac, e := normalize(frac) - exp += e - x := Float64bits(frac) - exp += int(x>>shift)&mask - bias - if exp < -1074 { - return Copysign(0, frac) // underflow - } - if exp > 1023 { // overflow - if frac < 0 { - return Inf(-1) - } - return Inf(1) - } - var m float64 = 1 - if exp < -1022 { // denormal - exp += 52 - m = 1.0 / (1 << 52) // 2**-52 - } - x &^= mask << shift - x |= uint64(exp+bias) << shift - return m * Float64frombits(x) -} |