[Help-gsl] Blitz library and GSL

[Paul Schneider]

Hello,

I would like to use blitz::Arrays (because of a couple of very 
convenient features) with the GSL linear algebra routines.  What's the 
best way of doing that? Blitz arrays provide a member function .data() 
which returns a pointer to the first element in the blitz array. I tried 
the following code to create a GSL view of the data in the blitz::array :

#include <iostream>
#include <cstdlib>
#include <blitz/array.h>
#include <gsl/gsl_linalg.h>

using namespace std;

int main(int argc, char *argv[])
{
   blitz::Array<double, 1> X(5);
   X = 1.08, 1.07, 0.97, 0.77, 0.84;
 cout << "A : " << X << endl;
 cout << "A data: " << X.data() << endl;

   gsl_vector_view m = gsl_vector_view_array (X.data(), 
X.extent(blitz::firstDim));

 cout << &m.vector.data << endl;
 for( int i = 0; i < m.vector.size ; ++i ){
     cout << gsl_vector_get(&m.vector, i) << endl;
 }
 return EXIT_SUCCESS;
}

Since I will have to work with huge matrices and vectors I would like to 
avoid copying as much as possible. Is there a better approach how to get 
stuff into GSL than the above code?

Second question: What's the most efficient way of constructing a GSL 
matrix out of raw C  vectors ?

Thanks very much for your help,

Paul