This is the mail archive of the gsl-discuss@sources.redhat.com mailing list for the GSL project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

forwarded message from Francisco J Molina


--- Begin Message ---
What I am trying to avoid is the call to gsl_vector_get for performance.
I think the stride should be 1. Is there any way I can check it?

Brian Gough writes:
 > Francisco J Molina writes:
 >  > In gsl_multiroot_function the prototype of the member function f 
 >  > is 
 >  > int f (gsl_vector * x, void * p, _matrix * f ).
 >  > 
 >  > I am trying to avoid the use of the function
 >  > gsl_vector_get ( x, 0 );
 >  > and supstitute it with 
 >  > pX = x->data;
 >  > pX [ 0 ];
 >  > Is this safe? Is the stride of x always 1?
 > 
 > If you want to avoid typing I'd recommend using 
 >   #define X(i) gsl_vector_get(x,(i)) 
 > or 
 >   #define VEC(x,i) gsl_vector_get((x),(i))
 > which don't rely on assumptions about the stride.
 > 
 > -- 
 > Brian


--- End Message ---

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]