LAPACK Archives

[Lapack] failed to build 32 bit f2clib

On Tue, 15 Jul 2008, Edwin Sarkissian wrote:

However, some of the lapack function calls never returned.
For example,  the executables that are included in the package
and are used to test the lapack library never end.

I wrote the following code (test.c)

       #include "f2c.h"
       #include "clapack.h"

       int main()
           integer m=3, n=2, nrhs=1, lda=3, ldb=3, lwork=512, info;
           double aa[]={1,1,1,2,3,4};
           double bb[]={2,3,4};
           double w[512];
           char trans='N';
           int result = dgels_( &trans, &m, &n, &nrhs, aa, &lda, bb,
&ldb, w, &lwork, &info );

           return, 0;

I compiled and linked the code without any error message with the command
       gcc test.c lapack_LINUX.a blas_LINUX.a F2CLIBS/libf2c.a -lm -IINCLUDE
but when I ran the executable a.out it never returned.  However,
after I changed
the initialization value of lwork to -1 and compiled and ran the
executable, then
it returned.  The argument lwork is set to -1 when we need the lapack
function to return an optimum size for work buffer only.

OK so

1- there is a problem with this code not returning without modification

2- when you perform your modification, the optimal worspace size is in 
w[0], not in lwork, lwork is input only so it is left unchanged in exit as 
you have observed.

I followed the same steps mentioned above exactly on a
i386 architecture / linux / 64 bit platform and all executables
ran to completion without any error or problem.

Great, great, great. I do not know what the problem 1 is ...


<Prev in Thread] Current Thread [Next in Thread>

For additional information you may use the LAPACK/ScaLAPACK Forum.
Or one of the mailing lists, or