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-rw-r--r--lib/mlibc/options/ansi/generic/complex/csqrt.c137
1 files changed, 0 insertions, 137 deletions
diff --git a/lib/mlibc/options/ansi/generic/complex/csqrt.c b/lib/mlibc/options/ansi/generic/complex/csqrt.c
deleted file mode 100644
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--- a/lib/mlibc/options/ansi/generic/complex/csqrt.c
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@@ -1,137 +0,0 @@
-/* $NetBSD: csqrt.c,v 1.1 2007/08/20 16:01:37 drochner Exp $ */
-
-/*-
- * Copyright (c) 2007 The NetBSD Foundation, Inc.
- * All rights reserved.
- *
- * This code is derived from software written by Stephen L. Moshier.
- * It is redistributed by the NetBSD Foundation by permission of the author.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
- * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
- * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- * imported and modified include for newlib 2010/10/03
- * Marco Atzeri <marco_atzeri@yahoo.it>
- */
-
-/*
-FUNCTION
- <<csqrt>>, <<csqrtf>>---complex square root
-
-INDEX
- csqrt
-INDEX
- csqrtf
-
-ANSI_SYNOPSIS
- #include <complex.h>
- double complex csqrt(double complex <[z]>);
- float complex csqrtf(float complex <[z]>);
-
-
-DESCRIPTION
- These functions compute the complex square root of <[z]>, with
- a branch cut along the negative real axis.
-
- <<csqrtf>> is identical to <<csqrt>>, except that it performs
- its calculations on <<floats complex>>.
-
-RETURNS
- The csqrt functions return the complex square root value, in
- the range of the right halfplane (including the imaginary axis).
-
-PORTABILITY
- <<csqrt>> and <<csqrtf>> are ISO C99
-
-QUICKREF
- <<csqrt>> and <<csqrtf>> are ISO C99
-
-*/
-
-
-#include <complex.h>
-#include <math.h>
-
-double complex
-csqrt(double complex z)
-{
- double complex w;
- double x, y, r, t, scale;
-
- x = creal (z);
- y = cimag (z);
-
- if (y == 0.0) {
- if (x == 0.0) {
- w = 0.0 + y * I;
- } else {
- r = fabs(x);
- r = sqrt(r);
- if (x < 0.0) {
- w = 0.0 + r * I;
- } else {
- w = r + y * I;
- }
- }
- return w;
- }
- if (x == 0.0) {
- r = fabs(y);
- r = sqrt(0.5 * r);
- if (y > 0)
- w = r + r * I;
- else
- w = r - r * I;
- return w;
- }
- /* Rescale to avoid internal overflow or underflow. */
- if ((fabs(x) > 4.0) || (fabs(y) > 4.0)) {
- x *= 0.25;
- y *= 0.25;
- scale = 2.0;
- } else {
-#if 1
- x *= 1.8014398509481984e16; /* 2^54 */
- y *= 1.8014398509481984e16;
- scale = 7.450580596923828125e-9; /* 2^-27 */
-#else
- x *= 4.0;
- y *= 4.0;
- scale = 0.5;
-#endif
- }
- w = x + y * I;
- r = cabs(w);
- if (x > 0) {
- t = sqrt(0.5 * r + 0.5 * x);
- r = scale * fabs((0.5 * y) / t );
- t *= scale;
- } else {
- r = sqrt(0.5 * r - 0.5 * x);
- t = scale * fabs((0.5 * y) / r);
- r *= scale;
- }
- if (y < 0)
- w = t - r * I;
- else
- w = t + r * I;
- return w;
-}