1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 24 */ 25 /* 26 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 27 * Use is subject to license terms. 28 */ 29 30 #pragma weak __ctan = ctan 31 32 /* INDENT OFF */ 33 /* 34 * dcomplex ctan(dcomplex z); 35 * 36 * If z = x+iy, then since ctan(iz) = i*ctanh(z), we have 37 * 38 * ctan(z) = ctan((-1)*(-z)) = ctan(i*i*(-z)) 39 * = i*ctanh(i*(-z)) = i*ctanh(i*(-x-yi)) 40 * = i*ctanh(y-ix) 41 * = -Im(ctanh(y-ix))+i*Re(ctanh(y-ix)) 42 */ 43 /* INDENT ON */ 44 45 #include "libm.h" 46 #include "complex_wrapper.h" 47 48 dcomplex 49 ctan(dcomplex z) { 50 double x, y; 51 dcomplex ans, ct; 52 53 x = D_RE(z); 54 y = D_IM(z); 55 D_RE(z) = y; 56 D_IM(z) = -x; 57 ct = ctanh(z); 58 D_RE(ans) = -D_IM(ct); 59 D_IM(ans) = D_RE(ct); 60 return (ans); 61 } 62