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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:23:18 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:23:18 +0000
commit43a123c1ae6613b3efeed291fa552ecd909d3acf (patch)
treefd92518b7024bc74031f78a1cf9e454b65e73665 /src/math/nextafter.go
parentInitial commit. (diff)
downloadgolang-1.20-43a123c1ae6613b3efeed291fa552ecd909d3acf.tar.xz
golang-1.20-43a123c1ae6613b3efeed291fa552ecd909d3acf.zip
Adding upstream version 1.20.14.upstream/1.20.14upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/math/nextafter.go')
-rw-r--r--src/math/nextafter.go51
1 files changed, 51 insertions, 0 deletions
diff --git a/src/math/nextafter.go b/src/math/nextafter.go
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+++ b/src/math/nextafter.go
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+// 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 are:
+//
+// 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 are:
+//
+// Nextafter(x, x) = x
+// Nextafter(NaN, y) = NaN
+// Nextafter(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
+}