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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 13:16:40 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 13:16:40 +0000 |
commit | 47ab3d4a42e9ab51c465c4322d2ec233f6324e6b (patch) | |
tree | a61a0ffd83f4a3def4b36e5c8e99630c559aa723 /src/math/hypot.go | |
parent | Initial commit. (diff) | |
download | golang-1.18-47ab3d4a42e9ab51c465c4322d2ec233f6324e6b.tar.xz golang-1.18-47ab3d4a42e9ab51c465c4322d2ec233f6324e6b.zip |
Adding upstream version 1.18.10.upstream/1.18.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/math/hypot.go')
-rw-r--r-- | src/math/hypot.go | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/src/math/hypot.go b/src/math/hypot.go new file mode 100644 index 0000000..12af177 --- /dev/null +++ b/src/math/hypot.go @@ -0,0 +1,43 @@ +// 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 + +/* + Hypot -- sqrt(p*p + q*q), but overflows only if the result does. +*/ + +// Hypot returns Sqrt(p*p + q*q), taking care to avoid +// unnecessary overflow and underflow. +// +// Special cases are: +// Hypot(±Inf, q) = +Inf +// Hypot(p, ±Inf) = +Inf +// Hypot(NaN, q) = NaN +// Hypot(p, NaN) = NaN +func Hypot(p, q float64) float64 { + if haveArchHypot { + return archHypot(p, q) + } + return hypot(p, q) +} + +func hypot(p, q float64) float64 { + // special cases + switch { + case IsInf(p, 0) || IsInf(q, 0): + return Inf(1) + case IsNaN(p) || IsNaN(q): + return NaN() + } + p, q = Abs(p), Abs(q) + if p < q { + p, q = q, p + } + if p == 0 { + return 0 + } + q = q / p + return p * Sqrt(1+q*q) +} |