libgo/go/math/signbit.go

   1 // Copyright 2010 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 // Signbit returns true if x is negative or negative zero.
   8 func Signbit(x float64) bool {
   9         return Float64bits(x)&(1<<63) != 0
  10 }