Guidance on building FORTRAN wrappers

[fletchjp]

I am wishing to run some routines such as magma_zcgesv from FORTRAN. There are wrappers for quite a lot of routines but not for this one.

I can see that the control subdirectory contains the files magma_zfortran.F90 and magma_zf77.cpp and it looks as though I can use some of the code there as a model to build my own wrappers. The macro FORTRAN_NAME is defined in include/magma_mangling.h

Are there any notes to follow to make a wrapper?

I may also want to build a modified version of magma_zcgesv and build a wrapper for that, compiling it outside magma. Would that be any different?

Thanks

John

[mgates3]

The attached may help. I just did these real quick with a script that we use, but they do at least compile. Let us know if you have any problems with them.
-mark

[fletchjp]

Mark

Thank you for the quick response. I have had a look at these files. Presumably I just compile and link these files into my code.

John

P.S. I am currently using Magma 1.6.2

[mgates3]

Yes. They mirror existing files in the control directory, adding Fortran wrappers for the mixed precision routines. We base the Fortran wrappers off the header files (e.g., include/magma_z.h), and the mixed routines have their own header files (e.g., include/magma_zc.h), which is why they weren't included before.

I don't think we've changed any of these routines since 1.6.2, so they should still work there.

-mark

[fletchjp]

Mark

Thank you for this. I will give these a try out.

John

[fletchjp]

I have built the attached Fortran program testing_zcgesv_gpu_f by extending the Fortran one for zgetrf_gpu with material suggested by the C++ one for zcgesv_gpu.

This routine does a similar calculation to the one in the Fortran one for zgetrf_gpu with magma_zcgesv_gpu as well and prints both sets of answers.

The output is like this:

Code: Select all

 size_of_int =            4
 ZCGESV iters :            3

 Solving A x = b using mixed precision factorization:
                         || A || =  1.063E+03
                         || b || =  9.994E-01
                         || x || =  1.908E+00
                   || b - A x || =  3.642E-14

   Gflops  =    38.019799967504056     

                Solution is CORRECT

 Solving A x = b using LU factorization:
                         || A || =  1.063E+03
                         || b || =  9.994E-01
                         || x || =  1.908E+00
                   || b - A x || =  9.535E-13

   Gflops  =    13.994576034374978     

                Solution is CORRECT

I hope this is useful

John

P.S. As this is my 200th message, I want to thank the MAGMA team for all your help over the years I have been in contact with you. Best wishes.