| // 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 |
| |
| // Modf returns integer and fractional floating-point numbers |
| // that sum to f. Both values have the same sign as f. |
| // |
| // Special cases are: |
| // Modf(+Inf) = +Inf, NaN |
| // Modf(-Inf) = -Inf, NaN |
| // Modf(NaN) = NaN, NaN |
| func Modf(f float64) (int float64, frac float64) { |
| if f < 1 { |
| if f < 0 { |
| int, frac = Modf(-f) |
| return -int, -frac |
| } |
| return 0, f |
| } |
| |
| x := Float64bits(f) |
| e := uint(x>>shift)&mask - bias |
| |
| // Keep the top 11+e bits, the integer part; clear the rest. |
| if e < 64-11 { |
| x &^= 1<<(64-11-e) - 1 |
| } |
| int = Float64frombits(x) |
| frac = f - int |
| return |
| } |