Re: Free AMD Core Math Library (BLAS/LAPACK) + Ada

[Simon Wright <simon@pushface.org>]

Ada novice <shai.lesh@gmx.com> writes:

> locate libblas
> /etc/alternatives/libblas.so.3gf
> /usr/lib/libblas
> /usr/lib/libblas.so.3gf
> /usr/lib/atlas-base/atlas/libblas.so.3gf
> /usr/lib/atlas-base/atlas/libblas.so.3gf.0
> /usr/lib/libblas/libblas.so.3gf
> /usr/lib/libblas/libblas.so.3gf.0

> Simon, I do not have libblas.a and libblas.so as you wrote in your
> last post that I should.

I have no idea how they got into my system! but that's what's missing.

When you say '-lblas' that tells the linker to look for libblas.so (or
maybe libblas.a, I'm not sure of the rules). It looks in various places;
the default will certainly include /usr/lib/.

I think we should create libblas.so there. You will need to do this as
root; be very careful! (if anyone else is listening and knows a better
way, please say so ...)

This sequence will create a symbolic link or symlink in /usr/lib/ so
that when the linker looks for libblas.so it finds it, and when it opens
it the system chases the symlink(s) until it finds a real file, which is
what gets opened. 'ln -s' creates a symlink; 'man ln' for more info.

Again, be careful. You may want to practice first, using your normal
account in some scratch directory.

   $ cd /usr/lib
   $ su
   Password:                   enter root's password here
   # ln -s libblas.so.3gf libblas.so
   # exit
   $

(I'm assuming that /usr/lib/libblas.so.3gf is at least a symlink to a
real library!)

It looks to me as though it's at least possible that the files in
/usr/lib/atlas-base/atlas/ and /usr/lib/libblas/ are in fact the
same.

> Now I do not make reference to ATLAS. So I modified my .bashrc as follows:
> cat $HOME/.bashrc
> export LD_LIBRARY_PATH=/usr/lib/i386-linux-gnu/:/usr/lib/libblas/
> export LIBRARY_PATH=/usr/lib/i386-linux-gnu/:/usr/lib/libblas/
>
> and I see the folder /usr/lib/libblas has the following files:
> libblas.so.3gf and libblas.so.3gf.0
>
> and echo $LIBRARY_PATH gives
> /usr/lib/i386-linux-gnu/:/usr/lib/libblas/

If we manage to create /usr/lib/libblas.so you shouldn't need any of
this. But it won't harm to leave it for the moment.

> So what should I do next?
>
> Should I uninstall ATLAS completely? Is the following a neat uninstall? :
>
> apt-get autoremove libatlas3gf-base 

I think I may have misled you here; I'd leave it alone for now.