Re: [Help-gsl] Test suite?

[Steven Vancoillie]

On Thursday 18 September 2008 01:11:22 Liam Healy wrote:
> I modified the function in poly/eval.c almost like this, but using z
> instead of x as that looks more correct and it is what is in the
> commented-out portion
> 
> gsl_complex
> gsl_complex_poly_complex_eval(const gsl_complex c[], const int len,
> const gsl_complex z)
> {
>   int i;
>   gsl_complex ans = c[len-1];
>   for(i=len-1; i>0; i--) {
>     /* The following three lines are equivalent to
>        ans = gsl_complex_add (c[i-1], gsl_complex_mul (z, ans));
>        but faster */
> 
>        ans = gsl_complex_add (c[i-1], gsl_complex_mul (z, ans));
> 
>        /*
>     double tmp = GSL_REAL (c[i-1]) + GSL_REAL (z) * GSL_REAL (ans) -
> GSL_IMAG (z) * GSL_IMAG (ans);
>     GSL_SET_IMAG (&ans, GSL_IMAG (c[i-1]) + GSL_IMAG (z) * GSL_REAL
> (ans) + GSL_REAL (z) * GSL_IMAG (ans));
>     GSL_SET_REAL (&ans, tmp);
>        */
>   }
>   return ans;
> }
> 
> However, when I make, it ends with
> make[2]: Entering directory `/home/liam/mathematics/gsl-1.11/poly'
> /bin/sh ../libtool --tag=CC   --mode=compile gcc -DHAVE_CONFIG_H -I.
> -I.. -I..    -g -O2 -c -o eval.lo eval.c
> libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I.. -I.. -g -O2 -c eval.c
> -fPIC -DPIC -o .libs/eval.o
> eval.c: In function 'gsl_complex_poly_complex_eval':
> eval.c:65: error: incompatible types in assignment
> make[2]: *** [eval.lo] Error 1
> make[2]: Leaving directory `/home/liam/mathematics/gsl-1.11/poly'
> make[1]: *** [all-recursive] Error 1
> make[1]: Leaving directory `/home/liam/mathematics/gsl-1.11'
> make: *** [all] Error 2
> 

Hi Liam,

If you change the code to use the functions gsl_complex_add and gsl_complex_mul,
then you have to use:
#include <gsl/gsl_complex_math.h>

grtz
Steven