X-Git-Url: http://nsz.repo.hu/git/?p=libm;a=blobdiff_plain;f=src%2Fcmath%2Fctanhf.c;fp=src%2Fcmath%2Fctanhf.c;h=7d746134b6d639fe9c418de48e5440fdef8ff62e;hp=0000000000000000000000000000000000000000;hb=5718e964d8a5c273a91b4d86d16926f54151c58f;hpb=1305df184d9d04274ce170864c92af8cbeae23e2 diff --git a/src/cmath/ctanhf.c b/src/cmath/ctanhf.c new file mode 100644 index 0000000..7d74613 --- /dev/null +++ b/src/cmath/ctanhf.c @@ -0,0 +1,66 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_ctanhf.c */ +/*- + * Copyright (c) 2011 David Schultz + * All rights reserved. + * + * 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 unmodified, 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 AUTHOR ``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 AUTHOR 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. + */ +/* + * Hyperbolic tangent of a complex argument z. See s_ctanh.c for details. + */ + +#include "libm.h" + +float complex ctanhf(float complex z) +{ + float x, y; + float t, beta, s, rho, denom; + uint32_t hx, ix; + + x = crealf(z); + y = cimagf(z); + + GET_FLOAT_WORD(hx, x); + ix = hx & 0x7fffffff; + + if (ix >= 0x7f800000) { + if (ix & 0x7fffff) + return cpackf(x, (y == 0 ? y : x * y)); + SET_FLOAT_WORD(x, hx - 0x40000000); + return cpackf(x, copysignf(0, isinf(y) ? y : sinf(y) * cosf(y))); + } + + if (!isfinite(y)) + return cpackf(y - y, y - y); + + if (ix >= 0x41300000) { /* x >= 11 */ + float exp_mx = expf(-fabsf(x)); + return cpackf(copysignf(1, x), 4 * sinf(y) * cosf(y) * exp_mx * exp_mx); + } + + t = tanf(y); + beta = 1.0 + t * t; + s = sinhf(x); + rho = sqrtf(1 + s * s); + denom = 1 + beta * s * s; + return cpackf((beta * rho * s) / denom, t / denom); +}