xref: /illumos-gate/usr/src/lib/libm/common/complex/ccos.c (revision 25c28e83beb90e7c80452a7c818c5e6f73a07dc8)
1*25c28e83SPiotr Jasiukajtis /*
2*25c28e83SPiotr Jasiukajtis  * CDDL HEADER START
3*25c28e83SPiotr Jasiukajtis  *
4*25c28e83SPiotr Jasiukajtis  * The contents of this file are subject to the terms of the
5*25c28e83SPiotr Jasiukajtis  * Common Development and Distribution License (the "License").
6*25c28e83SPiotr Jasiukajtis  * You may not use this file except in compliance with the License.
7*25c28e83SPiotr Jasiukajtis  *
8*25c28e83SPiotr Jasiukajtis  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9*25c28e83SPiotr Jasiukajtis  * or http://www.opensolaris.org/os/licensing.
10*25c28e83SPiotr Jasiukajtis  * See the License for the specific language governing permissions
11*25c28e83SPiotr Jasiukajtis  * and limitations under the License.
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13*25c28e83SPiotr Jasiukajtis  * When distributing Covered Code, include this CDDL HEADER in each
14*25c28e83SPiotr Jasiukajtis  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15*25c28e83SPiotr Jasiukajtis  * If applicable, add the following below this CDDL HEADER, with the
16*25c28e83SPiotr Jasiukajtis  * fields enclosed by brackets "[]" replaced with your own identifying
17*25c28e83SPiotr Jasiukajtis  * information: Portions Copyright [yyyy] [name of copyright owner]
18*25c28e83SPiotr Jasiukajtis  *
19*25c28e83SPiotr Jasiukajtis  * CDDL HEADER END
20*25c28e83SPiotr Jasiukajtis  */
21*25c28e83SPiotr Jasiukajtis 
22*25c28e83SPiotr Jasiukajtis /*
23*25c28e83SPiotr Jasiukajtis  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
24*25c28e83SPiotr Jasiukajtis  */
25*25c28e83SPiotr Jasiukajtis /*
26*25c28e83SPiotr Jasiukajtis  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
27*25c28e83SPiotr Jasiukajtis  * Use is subject to license terms.
28*25c28e83SPiotr Jasiukajtis  */
29*25c28e83SPiotr Jasiukajtis 
30*25c28e83SPiotr Jasiukajtis #pragma weak ccos = __ccos
31*25c28e83SPiotr Jasiukajtis 
32*25c28e83SPiotr Jasiukajtis /* INDENT OFF */
33*25c28e83SPiotr Jasiukajtis /*
34*25c28e83SPiotr Jasiukajtis  * dcomplex ccos(dcomplex z);
35*25c28e83SPiotr Jasiukajtis  *
36*25c28e83SPiotr Jasiukajtis  * z := x+iy; since ccos(iz) = cosh(z), we have
37*25c28e83SPiotr Jasiukajtis  * ccos(z)	= ccos((-1)*(-z)) = ccos(i*i*(-z))
38*25c28e83SPiotr Jasiukajtis  *		= ccosh(i*(-z)) = ccosh(i*(-x-yi))
39*25c28e83SPiotr Jasiukajtis  *		= ccosh(y-ix)
40*25c28e83SPiotr Jasiukajtis  */
41*25c28e83SPiotr Jasiukajtis /* INDENT ON */
42*25c28e83SPiotr Jasiukajtis 
43*25c28e83SPiotr Jasiukajtis #include "libm.h"
44*25c28e83SPiotr Jasiukajtis #include "complex_wrapper.h"
45*25c28e83SPiotr Jasiukajtis 
46*25c28e83SPiotr Jasiukajtis dcomplex
47*25c28e83SPiotr Jasiukajtis ccos(dcomplex z) {
48*25c28e83SPiotr Jasiukajtis 	double x, y;
49*25c28e83SPiotr Jasiukajtis 
50*25c28e83SPiotr Jasiukajtis 	x = D_RE(z);
51*25c28e83SPiotr Jasiukajtis 	y = D_IM(z);
52*25c28e83SPiotr Jasiukajtis 	D_RE(z) = y;
53*25c28e83SPiotr Jasiukajtis 	D_IM(z) = -x;
54*25c28e83SPiotr Jasiukajtis 	return (ccosh(z));
55*25c28e83SPiotr Jasiukajtis }
56