1 /* $NetBSD: catanl.c,v 1.1 2014/10/10 00:48:18 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2007 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software written by Stephen L. Moshier. 8 * It is redistributed by the NetBSD Foundation by permission of the author. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include "../src/namespace.h" 33 #include <complex.h> 34 #include <math.h> 35 #include <float.h> 36 #include "cephes_subrl.h" 37 38 #ifdef __weak_alias 39 __weak_alias(catanl, _catanl) 40 #endif 41 42 #define MAXNUM LDBL_MAX 43 44 long double complex 45 catanl(long double complex z) 46 { 47 long double complex w; 48 long double a, t, x, x2, y; 49 50 x = creall(z); 51 y = cimagl(z); 52 53 if ((x == 0.0L) && (y > 1.0L)) 54 goto ovrf; 55 56 x2 = x * x; 57 a = 1.0L - x2 - (y * y); 58 if (a == 0.0) 59 goto ovrf; 60 61 t = 0.5L * atan2l(2.0L * x, a); 62 w = _redupil(t); 63 64 t = y - 1.0L; 65 a = x2 + (t * t); 66 if (a == 0.0L) 67 goto ovrf; 68 69 t = y + 1.0L; 70 a = (x2 + (t * t))/a; 71 w = w + (0.25L * logl(a)) * I; 72 return w; 73 74 ovrf: 75 #if 0 76 mtherr ("catanl", OVERFLOW); 77 #endif 78 w = MAXNUM + MAXNUM * I; 79 return w; 80 } 81
