This is the mail archive of the
gsl-discuss@sources.redhat.com
mailing list for the GSL project.
Re: modifying matrix allocation functions for use with R
Faheem Mitha writes:
> Surely, this should be "...the input matrix A contain the matrix U"?
Thanks. Now fixed.
> Incidentally, it is a little awkward to compute the inverse of a matrix,
> since this involves calling both int gsl_linalg_LU_decomp and int
> gsl_linalg_LU_invert. Would it not be useful to have a "wrapper" function
> which uses both together?
Maybe, but in this case computing the inverse matrix is not something
I want to encourage, as it's usually better to solve Ax=b instead.
> I have one (slighly idle) question. I have noticed that macros are used
> quite liberally in the gsl source code, for example you have a macro
> called TYPE which seems to do nothing at all, there is another macro
> called PUNCTION(foo, bar) which concatenates foo and bar etc. I'm just
> wondering what purpose some of these serve, like the TYPE macro for
> example. Do they just make the code easier to write?
These macros are used to make the functions for different types,
gsl_vector_float, gsl_vector_int, etc. See the file templates_on.h
for details.
Brian