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(NaN) = NaN, NaN 13 func Modf(f float64) (int float64, frac float64) 14 15 func modf(f float64) (int float64, frac float64) { 16 if f < 1 { 17 if f < 0 { 18 int, frac = Modf(-f) 19 return -int, -frac 20 } 21 return 0, f 22 } 23 24 x := Float64bits(f) 25 e := uint(x>>shift)&mask - bias 26 27 // Keep the top 12+e bits, the integer part; clear the rest. 28 if e < 64-12 { 29 x &^= 1<<(64-12-e) - 1 30 } 31 int = Float64frombits(x) 32 frac = f - int 33 return 34 }