topic Re: C interface for LAPACK routines? in Intel® oneAPI Math Kernel Library

C interface for LAPACK routines?

ltkeene — Mon, 06 Oct 2008 18:20:57 GMT

Hello all, I've downloaded a trial verison of the latest release of MKL but find the documentation very disjointed and confusing. At the moment I simply need to solve a small (3x3) system of linear equations. Is there a C interface for the LAPACK routines (where I assume I find this functionality)? The documentation only talks about Fortran.

Thank you in advance.

Re: C interface for LAPACK routines?

Gennady_F_Intel — Tue, 07 Oct 2008 10:57:11 GMT

Yes, the documentation only talks only about Fortran, because of there are no special C interface, but you can use Fortran interface from C code.

As an example please look at the Forum question ( http://software.intel.com/en-us/forums/showthread.php?t=61117)where MKL customer call dgesvx rountine from C code.

--Gennady

Re: C interface for LAPACK routines?

TimP — Tue, 07 Oct 2008 13:24:43 GMT

Quoting - ltkeene

You could use the Clapack interface with MKL, if that is your question. MKL would be an inefficient way to work with such a small system anyway. As MKL BLAS is a work-alike implementation of the public netlib BLAS, the public documentation applies.

Re: C interface for LAPACK routines?

Gennady_F_Intel — Wed, 08 Oct 2008 05:43:13 GMT

As an additional info:

CLapack intefaces you find into mkl_lapack.h, but as I said

MKL documentation contains only Fortran interface description. As an example the function for computes the solution to the system of linear equations with a square matrix A and multiple right-hand sides, and provides error bounds on the solution.

//mkl_lapack.h

//void dgesvx( char *fact, char *trans, MKL_INT *n, MKL_INT *nrhs, double *a, MKL_INT *lda, double *af, MKL_INT *ldaf, MKL_INT *ipiv, char *equed, double *r, double *c, double *b, MKL_INT *ldb, double *x, MKL_INT *ldx, double *rcond, double *ferr, double *berr, double *work, MKL_INT *iwork, MKL_INT *info );

But all parameters of this function you can find into MKL manual for Fortran 77 or F95:

//Fortran 77

//call dgesvx( fact, trans, n, nrhs, a, lda, af, ldaf, ipiv, equed, r, c, b, ldb, x, ldx, rcond, ferr, berr, work, iwork, info )

Gennady

Re: C interface for LAPACK routines?

Gennady_F_Intel — Tue, 14 Oct 2008 03:12:42 GMT

Hello. please pay attention on the topic

http://software.intel.com/en-us/forums/showthread.php?t=61234

Todd posted yesterday about C interface for LAPACK routines.

Please send your recomendations to Michael and Creg about that.

--Gennady