60 lines
1.2 KiB
C
60 lines
1.2 KiB
C
/* $NetBSD: carg.c,v 1.1 2007/08/20 16:01:31 drochner Exp $ */
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/*
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* Written by Matthias Drochner <drochner@NetBSD.org>.
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* Public domain.
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*
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* imported and modified include for newlib 2010/10/03
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* Marco Atzeri <marco_atzeri@yahoo.it>
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*/
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/*
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FUNCTION
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<<carg>>, <<cargf>>---argument (phase angle)
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INDEX
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carg
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INDEX
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cargf
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ANSI_SYNOPSIS
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#include <complex.h>
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double carg(double complex <[z]>);
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float cargf(float complex <[z]>);
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DESCRIPTION
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These functions compute the argument (also called phase angle)
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of <[z]>, with a branch cut along the negative real axis.
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<<cargf>> is identical to <<carg>>, except that it performs
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its calculations on <<floats complex>>.
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RETURNS
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@ifnottex
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The carg functions return the value of the argument in the
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interval [-pi, +pi]
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@end ifnottex
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@tex
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The carg functions return the value of the argument in the
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interval [$-\pi$, $+\pi$]
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@end tex
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PORTABILITY
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<<carg>> and <<cargf>> are ISO C99
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QUICKREF
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<<carg>> and <<cargf>> are ISO C99
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*/
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#include <complex.h>
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#include <math.h>
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double
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carg(double complex z)
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{
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return atan2( cimag(z) , creal(z) );
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}
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