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authormartynas <martynas@openbsd.org>2008-09-07 20:36:06 +0000
committermartynas <martynas@openbsd.org>2008-09-07 20:36:06 +0000
commit7b36286a70b46b494e2bca4a889ab49ef62ba86c (patch)
treeb2b9870e3495ed88715e57b0d4a9888b16264fe0 /lib/libm/src/s_catanf.c
parentsparc now requires this bloated library to be -fPIC (diff)
downloadwireguard-openbsd-7b36286a70b46b494e2bca4a889ab49ef62ba86c.tar.xz
wireguard-openbsd-7b36286a70b46b494e2bca4a889ab49ef62ba86c.zip
- replace dtoa w/ David's gdtoa, version 2008-03-15
- provide proper dtoa locks - use the real strtof implementation - add strtold, __hdtoa, __hldtoa - add %a/%A support - don't lose precision in printf, don't round to double anymore - implement extended-precision versions of libc functions: fpclassify, isnan, isinf, signbit, isnormal, isfinite, now that the ieee.h is fixed - separate vax versions of strtof, and __hdtoa - add complex math support. added functions: cacos, casin, catan, ccos, csin, ctan, cacosh, casinh, catanh, ccosh, csinh, ctanh, cexp, clog, cabs, cpow, csqrt, carg, cimag, conj, cproj, creal, cacosf, casinf, catanf, ccosf, csinf, ctanf, cacoshf, casinhf, catanhf, ccoshf, csinhf, ctanhf, cexpf, clogf, cabsf, cpowf, csqrtf, cargf, cimagf, conjf, cprojf, crealf - add fdim, fmax, fmin - add log2. (adapted implementation e_log.c. could be more acruate & faster, but it's good enough for now) - remove wrappers & cruft in libm, supposed to work-around mistakes in SVID, etc.; use ieee versions. fixes issues in python 2.6 for djm@ - make _digittoint static - proper definitions for i386, and amd64 in ieee.h - sh, powerpc don't really have extended-precision - add missing definitions for mips64 (quad), m{6,8}k (96-bit) float.h for LDBL_* - merge lead to frac for m{6,8}k, for gdtoa to work properly - add FRAC*BITS & EXT_TO_ARRAY32 definitions in ieee.h, for hdtoa&ldtoa to use - add EXT_IMPLICIT_NBIT definition, which indicates implicit normalization bit - add regression tests for libc: fpclassify and printf - arith.h & gd_qnan.h definitions - update ieee.h: hppa doesn't have quad-precision, hppa64 does - add missing prototypes to gdtoaimp - on 64-bit platforms make sure gdtoa doesn't use a long when it really wants an int - etc., what i may have forgotten... - bump libm major, due to removed&changed symbols - no libc bump, since this is riding on djm's libc major crank from a day ago discussed with / requested by / testing theo, sthen@, djm@, jsg@, merdely@, jsing@, tedu@, brad@, jakemsr@, and others. looks good to millert@ parts of the diff ok kettenis@ this commit does not include: - man page changes
Diffstat (limited to 'lib/libm/src/s_catanf.c')
-rw-r--r--lib/libm/src/s_catanf.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/lib/libm/src/s_catanf.c b/lib/libm/src/s_catanf.c
new file mode 100644
index 00000000000..e112e7f090a
--- /dev/null
+++ b/lib/libm/src/s_catanf.c
@@ -0,0 +1,124 @@
+/* $OpenBSD: s_catanf.c,v 1.1 2008/09/07 20:36:09 martynas Exp $ */
+/*
+ * Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* catanf()
+ *
+ * Complex circular arc tangent
+ *
+ *
+ *
+ * SYNOPSIS:
+ *
+ * float complex catanf();
+ * float complex z, w;
+ *
+ * w = catanf( z );
+ *
+ *
+ *
+ * DESCRIPTION:
+ *
+ * If
+ * z = x + iy,
+ *
+ * then
+ * 1 ( 2x )
+ * Re w = - arctan(-----------) + k PI
+ * 2 ( 2 2)
+ * (1 - x - y )
+ *
+ * ( 2 2)
+ * 1 (x + (y+1) )
+ * Im w = - log(------------)
+ * 4 ( 2 2)
+ * (x + (y-1) )
+ *
+ * Where k is an arbitrary integer.
+ *
+ *
+ *
+ * ACCURACY:
+ *
+ * Relative error:
+ * arithmetic domain # trials peak rms
+ * IEEE -10,+10 30000 2.3e-6 5.2e-8
+ *
+ */
+
+#include <complex.h>
+#include <math.h>
+
+#define MAXNUMF 1.0e38F
+
+static const double DP1 = 3.140625;
+static const double DP2 = 9.67502593994140625E-4;
+static const double DP3 = 1.509957990978376432E-7;
+
+static float
+_redupif(float xx)
+{
+ float x, t;
+ long i;
+
+ x = xx;
+ t = x/(float)M_PI;
+ if(t >= 0.0)
+ t += 0.5;
+ else
+ t -= 0.5;
+
+ i = t; /* the multiple */
+ t = i;
+ t = ((x - t * DP1) - t * DP2) - t * DP3;
+ return(t);
+}
+
+float complex
+catanf(float complex z)
+{
+ float complex w;
+ float a, t, x, x2, y;
+
+ x = creal (z);
+ y = cimag (z);
+
+ if((x == 0.0f) && (y > 1.0f))
+ goto ovrf;
+
+ x2 = x * x;
+ a = 1.0f - x2 - (y * y);
+ if (a == 0.0f)
+ goto ovrf;
+
+ t = 0.5f * atan2f(2.0f * x, a);
+ w = _redupif(t);
+
+ t = y - 1.0f;
+ a = x2 + (t * t);
+ if(a == 0.0f)
+ goto ovrf;
+
+ t = y + 1.0f;
+ a = (x2 + (t * t))/a;
+ w = w + (0.25f * logf (a)) * I;
+ return (w);
+
+ovrf:
+ /*mtherr( "catanf", OVERFLOW );*/
+ w = MAXNUMF + MAXNUMF * I;
+ return (w);
+}