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
5package math
6
7// Signbit reports whether x is negative or negative zero.
8func Signbit(x float64) bool {
9	return Float64bits(x)&(1<<63) != 0
10}
11