diff options
Diffstat (limited to 'src/math/big/float.go')
| -rw-r--r-- | src/math/big/float.go | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/src/math/big/float.go b/src/math/big/float.go index a89ef1021a..015f1645b6 100644 --- a/src/math/big/float.go +++ b/src/math/big/float.go @@ -219,22 +219,24 @@ func (x *Float) MantExp() (mant *Float, exp int) { return } -// SetMantExp is the inverse of MantExp. It sets z to mant × 2**exp and -// and returns z. The result z has the same precision and rounding mode -// as mant. +// SetMantExp sets z to mant × 2**exp and and returns z. +// The result z has the same precision and rounding mode +// as mant. SetMantExp is an inverse of MantExp but does +// not require 0.5 <= |mant| < 1.0. Specifically: +// +// new(Float).SetMantExp(x.MantExp()).Cmp(x) == 0 // // Special cases are: // // z.SetMantExp( ±0, exp) = ±0 // z.SetMantExp(±Inf, exp) = ±Inf // -// The result is ±Inf if the magnitude of exp is > MaxExp. func (z *Float) SetMantExp(mant *Float, exp int) *Float { z.Copy(mant) if len(z.mant) == 0 || z.exp == infExp { return z } - z.setExp(int64(exp)) + z.setExp(int64(z.exp) + int64(exp)) return z } |