/*ident "@(#)cls4:lib/complex/complex/abs.c 1.3" */ /******************************************************************************* C++ source for the C++ Language System, Release 3.0. This product is a new release of the original cfront developed in the computer science research center of AT&T Bell Laboratories. Copyright (c) 1993 UNIX System Laboratories, Inc. Copyright (c) 1991, 1992 AT&T and UNIX System Laboratories, Inc. Copyright (c) 1984, 1989, 1990 AT&T. All Rights Reserved. THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE of AT&T and UNIX System Laboratories, Inc. The copyright notice above does not evidence any actual or intended publication of such source code. *******************************************************************************/ #include #include "const.h" double abs(complex z) { register double temp; register double r = z.re; register double i = z.im; if (r < 0) r = -r; if (i == 0) return r; if (i < 0) i = -i; if (r == 0) return i; if (i > r) { temp = r; r = i; i = temp; } temp = i/r; temp = r*sqrt(1.0 + temp*temp); /*overflow!!*/ return temp; } double norm(complex z) { register double r = z.re; register double i = z.im; #define SAFE 6.521908912666391000e+18 /* 0.5*sqrt(GREATEST)*/ if (r