intel mkl pardiso to obtain determinant of matrix

[chao_n_]

I recently used the eigen with intel mkl pardiso to perform LDLT decomposition. It's much faster than other packages. I want to obtain the lower triangular matrix (matrixL) and diagonal matrix (vectorD) to calculate the determinant. Is it possible for intel mkl pardiso to obtain these two matrixes and how? Thanks.

[VidyalathaB_Intel]

Hi,

Thanks for reaching out to us.

>> diagonal matrix (vectorD)

You can make use of the routine pardiso_getdiag which returns the diagonal elements of the matrix.

https://www.intel.com/content/www/us/en/develop/documentation/onemkl-developer-reference-c/top/sparse-solver-routines/onemkl-pardiso-parallel-direct-sparse-solver-iface/pardiso-getdiag.html

At present, there are no functions available for PARDISO API which can return LU factors.

Here are some of the forum threads where similar questions have been discussed.

https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/MKL-PARDISO-get-L-U-factors/m-p/1265720#M31046

https://community.intel.com/t5/Intel-oneAPI-Math-Kernel-Library/Accessing-the-LU-factors-in-sparse-direct-solver/m-p/1279535#M31279

>>to obtain determinant of matrix

Since you want to compute the determinant maybe you can try DSS API (which is an alternative to PARDISO interface) dss_statistics https://www.intel.com/content/www/us/en/develop/documentation/onemkl-developer-reference-c/top/sparse-solver-routines/direct-sparse-solver-dss-interface-routines/dss-routines/dss-statistics.html#dss-statistics

Regards,

Vidya.

[chao_n_]

Many thanks for your answers. I have some additional questions.

What's the difference between PARDISO API and DSS API?

 Does DSS API also use multi-thread?

Which is much faster?

Will PARDISO API add determinant function in the future?

[VidyalathaB_Intel]

Hi,

>>....function in the future?

We are working on your issue. we will get back to you soon.

Regards,

Vidya.

[chao_n_]

Hi,

Thanks for your answer. You have missed some questions.

1) Does DSS API also use multi-thread?

2) What's the difference between PARDISO API and DSS API? Which is much faster?

[Ruqiu_C_Intel]

Hi,

1) Does DSS API also use multi-thread?

>>Yes, DSS API supports multi-thread.

2) What's the difference between PARDISO API and DSS API? Which is much faster?

>>DSS API is some kind of simplified API for beginners. Intel PARDISO API supports more options/features compare with DSS API.

Have a good day.

[Ruqiu_C_Intel · Accepted solution]

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