github.com/liujq9674git/golang-src-1.7@v0.0.0-20230517174348-17f6ec47f3f8/src/math/signbit.go (about)

     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  }