Re: const gsl_vector *

[Patrick Alken]

Also, the compiler should issue warnings/errors if you try to change 
anything else in the gsl_vector container. And since gsl_vector_set is 
the preferred way to set data elements, it will certainly detect a 
problem if you try to call gsl_vector_set on a const gsl_vector*

I think the main purpose of the current design was to abstract away all 
the details of gsl_vector, so in principle the user will never need to 
directly access the variables in v or directly access v->data. In 
practice, however, sometimes it is necessary to directly use those 
parameters.