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## [Help-gsl] Help-gsl Eigenvectors and eigenvalues

 From: Luke Subject: [Help-gsl] Help-gsl Eigenvectors and eigenvalues Date: Thu, 18 Jun 2015 07:14:49 +0000 (UTC) User-agent: Loom/3.14 (http://gmane.org/)

```Hello

I am using this example taken from gsl-ref.pdf:

#include <iostream>
#include <stdio.h>
#include <gsl/gsl_math.h>
#include <gsl/gsl_eigen.h>

int main (void)
{
double data[] = {
1.0 , 1/2.0, 1/3.0, 1/4.0,
1/2.0, 1/3.0, 1/4.0, 1/5.0,
1/3.0, 1/4.0, 1/5.0, 1/6.0,
1/4.0, 1/5.0, 1/6.0, 1/7.0
};
gsl_matrix_view m
= gsl_matrix_view_array (data, 4, 4);
gsl_vector *eval = gsl_vector_alloc (4);
gsl_matrix *evec = gsl_matrix_alloc (4, 4);
gsl_eigen_symmv_workspace * w =
gsl_eigen_symmv_alloc (4);
gsl_eigen_symmv (&m.matrix, eval, evec, w);
gsl_eigen_symmv_free (w);
gsl_eigen_symmv_sort (eval, evec,
GSL_EIGEN_SORT_ABS_ASC);
{
int i;
for (i = 0; i < 4; i++)
{
double eval_i
= gsl_vector_get (eval, i);
gsl_vector_view evec_i
= gsl_matrix_column (evec, i);
printf ("eigenvalue = %g\n", eval_i);
printf ("eigenvector = \n");
gsl_vector_fprintf (stdout,
&evec_i.vector, "%g");
}
}

return 0;
}

When I run the program I see:

eigenvalue = 6.94149e-308
eigenvector =

Process returned -1073741819 (0xC0000005)   execution time : 2.658 s
Press any key to continue.

For other example codes like:

computing the value of the Bessel function J0(x)
or
FFT routines for complex data

taken from gsl-ref.pdf
everything is fine.

I am using gsl-1.8 on Windows 8 64-bit.

I would be grateful for any help.
Best regards,
Luke

```