topic Re: Unable to run BLAS and LAPACK examples in Intel® Fortran Compiler

Unable to run BLAS and LAPACK examples

Feng__Jesse — Wed, 03 Jul 2024 01:42:18 GMT

I just learned that Intel has LAPACK installed in the oneAPI base toolkit but when testing the example codes such as https://www.intel.com/content/www/us/en/docs/onemkl/developer-reference-fortran/2024-2/blas-code-examples.html and https://www.intel.com/content/www/us/en/docs/onemkl/code-samples-lapack/2024-1/cgesv-example-fortran.html I am unable to compile. I get the following errors:

Severity Code Description Project File Line Suppression State
Error error LNK2019: unresolved external symbol SDOT referenced in function SDOT.void Test.obj

Severity Code Description Project File Line Suppression State
Error error LNK2019: unresolved external symbol CGESV referenced in function CGESV.t272p.t273p.t274p.t275p.t276p.t277p.t278p.t279p Test.obj

I simply created a main program code Fortran project and pasted the example codes in and saved the source code as test.for.

I double checked the installation and confirmed that I used default which did install the Intel MKL when I installed base and HPC toolkits. How do I properly link these libraries? I tried to read the documentation for Intel MKL and I failed to find the page that gave instructions on linking the libraries, if anyone can point me to the page that would also work. Thanks!

Re: Unable to run BLAS and LAPACK examples

andrew_4619 — Wed, 03 Jul 2024 08:56:26 GMT

You need to tell the project you are using mkl:

Re: Unable to run BLAS and LAPACK examples

Feng__Jesse — Wed, 03 Jul 2024 13:53:47 GMT

Thanks, Andrew. Is dgeqrf the QR decomposition subroutine? More importantly, the ?geqrf page says the subroutines return "elementary reflectors for Q", does that mean it uses the householder reflection implementation? I currently have a custom-implemented QR decomposition using the Gram-Schmidt approach but it can become unstable while the householder approach should be much better.

Re: Unable to run BLAS and LAPACK examples

andrew_4619 — Wed, 03 Jul 2024 14:01:33 GMT

My knowledge of mkl routines is pretty minimal, there are some on here that have in depth knowledge but there is also an mkl forum.