Howto make a cross prod with gsl ?

[Jean-Max Redonnet]

Hello, 

I'm a new user of gsl I will try to use for differential geometry 
computations.
Maybe I'm wrong, but I've not found a prebuilt function to perform cross 
product between vectors... ...so I've write one :

int vcross(gsl_vector *u, gsl_vector *v)
{
  double u_0, u_1, u_2;
  double v_0, v_1, v_2;

  u_0 = gsl_vector_get(u, 0);
  u_1 = gsl_vector_get(u, 1);
  u_2 = gsl_vector_get(u, 2);
  v_0 = gsl_vector_get(v, 0);
  v_1 = gsl_vector_get(v, 1);
  v_2 = gsl_vector_get(v, 2);
  
  gsl_vector_set(u, 0, u_1*v_2 - u_2*v_1);
  gsl_vector_set(u, 1, u_2*v_0 - u_0*v_2);
  gsl_vector_set(u, 2, u_0*v_1 - u_1*v_0);
  
  return GSL_SUCCESS;
}

This works fine, but I wonder if there is a best way to do that.

Thanks for any remark.

jmr

-- 
______________________________________________________________________________
Jean-Max Redonnet                             mailto:redonnet@lgmt.ups-tlse.fr
Mechanical Engineering Laboratory of Toulouse
University Paul Sabatier - Toulouse (France)