lapack 3.0

James R. Phillips antiskid56-cygwin@yahoo.com
Wed Jun 29 22:40:00 GMT 2005


--- "Gerrit P. Haase"  wrote:

> 
> No subdirectories below /usr/bin, please.
> 

OK, could you live with /usr/lib/lapack?

> To be honest, I cannot follow the discussion.  Why is it not possible to
> put the DLLs into /usr/bin?  Is there another official package which
> includes the same libraries?
> 

The design of the package is to install official nonoptimized binaries built
from lapack source.  But then to also allow local build and installation of
optimized atlas library versions if the source package is downloaded and
installed.  In order to accomplish this, the lapack and atlas source trees are
merged in the source package.

If/when optimized dll's created by atlas are installed, we want them to be used
instead of the nonoptimized libraries, but we don't really want to delete the
nonoptimized libraries.  So we would like to put them in /usr/local/bin, and
have the path string take care of the problem for us (/usr/local/bin precedes
/usr/bin in the path defined by /etc/profile).

If we were on *nix, we would be done.  But, we aren't.  It has been pointed out
that if a binary lives in /usr/bin, and uses the lapack dll, it will
immediately find the nonoptimized version, if that version lives in /usr/bin,
because windows always searches the current directory before the path.  So, the
initial approach needs to be modified: we don't want the nonoptimized binaries
to live in /usr/bin, because we want to be able to override them, but not
delete them, with a local install.  These leads us to consider /usr/lib/lapack.
 Such a solution will work, but requires a script in /etc/profile.d to put
/usr/lib/lapack in the path, at the back, so it will be preceded by
/usr/local/bin.  Then if/when optimized dlls are installed in /usr/local/bin,
they will be found before the default nonoptimized ones.

Thanks for the feedback on /usr/bin/lapack, I'll scratch that off, and make it
/usr/lib/lapack, unless someone has a problem with that.



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