| // Copyright 2015 The Go Authors. All rights reserved. | |
| // Use of this source code is governed by a BSD-style | |
| // license that can be found in the LICENSE file. | |
| package mathx | |
| // Sign returns the sign of x: -1 if x < 0, 0 if x == 0, 1 if x > 0. | |
| // If x is NaN, it returns NaN. | |
| func Sign(x float64) float64 { | |
| if x == 0 { | |
| return 0 | |
| } else if x < 0 { | |
| return -1 | |
| } else if x > 0 { | |
| return 1 | |
| } | |
| return nan | |
| } |