Missing dormqr equivalent in MKL Compact API for QR-based Batch Solve

[ivanp]

I would like to solve a batch of (square) linear systems using the compact/interleaved QR factorization routine, mkl_?geqrf_compact. However, I am struggling to find the documented "compact" way to complete the linear system solve AX=B using the QR factorization. The matrices I'm interested in have a strange structure, meaning that the non-pivoting LU factorization is not applicable.

In standard LAPACK, I would use dormqr to compute Q^T B and then dtrsm for the back-substitution R X = (Q^T B).

Additionally, are there any technical white papers or articles (for instance, in Intel Parallel Universe Magazine) that provide a deep dive into the Compact/Interleaved solver suite?

Thank in advance for any advice.

[ivanp]

Is there any chance this could be part of the oneMKL 2026.0 release? 

Essentially, what I'd need is similar to the ArmPL function,

• armpl_dormqr_interleave_batch

or in MKL API, this would be

• mkl_?ormqr_compact

[Chao_Y_Intel]

Hi @ivanp 

Thanks for submitting this request. We’ve tracked this request in our internal systems so it can be reviewed as part of our regular planning process.  Given other higher‑priority items, this feature has not been planned for near-term implementation yet.

In the meantime, if you have a Priority Support account, you may also submit questions through our Priority Support channel at https://supporttickets.intel.com/ for faster response on technical issues and product-related inquiries.

Regards,
Chao Y.

Intel MKL Support