gsl_function

[Patrick Dupre]

Hello,

I need to return a complex with a gsl_function.
How can I do?

Here is an example

#include <math.h>
#include <stdio.h>
#include <complex.h>
#include <gsl/gsl_integration.h>

double complex tt (double complex z) {
  double complex y = 0 ;
  for (unsigned short int i = 0 ; i < 5 ; i++) {
    y += z ;
    }
  return y ;
  }

main () {
  gsl_function fcn ;
  double complex y0 = 1 + I * 0.5 ;
  fcn.function = &tt ;
  double complex z = tt (y0) ;
  double complex zz = (double complex) fcn.function (y0, fcn.params) ;
  printf ("%g %g, %g %g\n", z, zz) ;
  }

Result (zz is not correct)
5 2.5, 5 0

Some ideas?

Thanks

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 Patrick DUPRÉ                                 | | email: pdupre@gmx.com
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