1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
|
// Copyright 2010 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 math
// Nextafter32 returns the next representable float32 value after x towards y.
// Special cases:
// Nextafter32(x, x) = x
// Nextafter32(NaN, y) = NaN
// Nextafter32(x, NaN) = NaN
func Nextafter32(x, y float32) (r float32) {
switch {
case IsNaN(float64(x)) || IsNaN(float64(y)): // special case
r = float32(NaN())
case x == y:
r = x
case x == 0:
r = float32(Copysign(float64(Float32frombits(1)), float64(y)))
case (y > x) == (x > 0):
r = Float32frombits(Float32bits(x) + 1)
default:
r = Float32frombits(Float32bits(x) - 1)
}
return
}
// Nextafter returns the next representable float64 value after x towards y.
// Special cases:
// Nextafter64(x, x) = x
// Nextafter64(NaN, y) = NaN
// Nextafter64(x, NaN) = NaN
func Nextafter(x, y float64) (r float64) {
switch {
case IsNaN(x) || IsNaN(y): // special case
r = NaN()
case x == y:
r = x
case x == 0:
r = Copysign(Float64frombits(1), y)
case (y > x) == (x > 0):
r = Float64frombits(Float64bits(x) + 1)
default:
r = Float64frombits(Float64bits(x) - 1)
}
return
}
|
