Source file src/pkg/math/modf.go
1 // Copyright 2009 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package math 6 7 // Modf returns integer and fractional floating-point numbers 8 // that sum to f. Both values have the same sign as f. 9 // 10 // Special cases are: 11 // Modf(+Inf) = +Inf, NaN 12 // Modf(-Inf) = -Inf, NaN 13 // Modf(NaN) = NaN, NaN 14 func Modf(f float64) (int float64, frac float64) { 15 if f < 1 { 16 if f < 0 { 17 int, frac = Modf(-f) 18 return -int, -frac 19 } 20 return 0, f 21 } 22 23 x := Float64bits(f) 24 e := uint(x>>shift)&mask - bias 25 26 // Keep the top 12+e bits, the integer part; clear the rest. 27 if e < 64-12 { 28 x &^= 1<<(64-12-e) - 1 29 } 30 int = Float64frombits(x) 31 frac = f - int 32 return 33 }