xref: /csrg-svn/usr.bin/f77/libF77/z_log.c (revision 47940)
1*47940Sbostic /*-
2*47940Sbostic  * Copyright (c) 1980 The Regents of the University of California.
3*47940Sbostic  * All rights reserved.
422999Skre  *
5*47940Sbostic  * %sccs.include.proprietary.c%
610552Sdlw  */
710552Sdlw 
8*47940Sbostic #ifndef lint
9*47940Sbostic static char sccsid[] = "@(#)z_log.c	5.3 (Berkeley) 04/12/91";
10*47940Sbostic #endif /* not lint */
11*47940Sbostic 
1210552Sdlw #include "complex"
1329972Smckusick #ifdef tahoe
1429972Smckusick #define cabs zabs
1529972Smckusick #endif tahoe
1610552Sdlw 
z_log(r,z)1710552Sdlw z_log(r, z)
1810552Sdlw dcomplex *r, *z;
1910552Sdlw {
2010552Sdlw double log(), cabs(), atan2();
2110552Sdlw 
2210552Sdlw r->dimag = atan2(z->dimag, z->dreal);
2310552Sdlw r->dreal = log( cabs( z->dreal, z->dimag ) );
2410552Sdlw }
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