newlib/libm/complex/conj.c

   1 /* $NetBSD: conj.c,v 1.2 2010/09/15 16:11:29 christos Exp $ */
   2
   3 /*
   4  * Written by Matthias Drochner <drochner@NetBSD.org>.
   5  * Public domain.
   6  *
   7  * imported and modified include for newlib 2010/10/03
   8  * Marco Atzeri <marco_atzeri@yahoo.it>
   9  */
  10
  11 /*
  12 FUNCTION
  13         <<conj>>, <<conjf>>---complex conjugate
  14
  15 INDEX
  16         conj
  17 INDEX
  18         conjf
  19
  20 SYNOPSIS
  21        #include <complex.h>
  22        double complex conj(double complex <[z]>);
  23        float complex conjf(float complex <[z]>);
  24
  25
  26 DESCRIPTION
  27         These functions compute the complex conjugate of <[z]>,
  28         by reversing the sign of its imaginary part.
  29
  30         <<conjf>> is identical to <<conj>>, except that it performs
  31         its calculations on <<floats complex>>.
  32
  33 RETURNS
  34         The conj functions return the complex conjugate value.
  35
  36 PORTABILITY
  37         <<conj>> and <<conjf>> are ISO C99
  38
  39 QUICKREF
  40         <<conj>> and <<conjf>> are ISO C99
  41
  42 */
  43
  44 #include <complex.h>
  45 #include "../common/fdlibm.h"
  46
  47 double complex
  48 conj(double complex z)
  49 {
  50         double_complex w = { .z = z };
  51
  52         IMAG_PART(w) = -IMAG_PART(w);
  53
  54         return (w.z);
  55 }