As discussed in this thread (https://www.mystran.com/forums/showthread.php?tid=6), one of the top priorities is to address the sparse solver.

For small DOF problems, this card "PARAM, SOLLIB, ZZPACK" can be used and is reliable (banded solver). However, for larger DOF programs, a sparse solver may be required. MYSTRAN currently uses an older Intel solver for this case (this only exists for the complied EXE but ***NOT*** for the files on GitHub, which is a known issue). However, this older sparse solver is not very reliable. This challenge has increased in priority because we can not use the older Intel MKL solver that Bill used in the past (so MYSTRAN only has the banded solvers LAPACK/ARPACK).

We are investigating various sparse solvers. We previously looked at BCSLIB-EXT, but the cost is relatively high and it appears there may be other solvers that are just as good (if not better).

1. The SPOOLES solver is an option, but it seems to be relatively slow compared to other options.

2. PARDSIO with Intel MKL is an option, but requires an Intel compiler and the user must also download the Intel MKL (personal information is required).

3. PARDISO 6 is more improved than PARDISO MKL, but requires the user download a free license every year (personal information is required).

4. PaStiX may be the best option since it is modern and free. We can take a page from CalculiX and see how their investigation is going since they looking at other solvers.

CalculiX has historically used SPOOLES, but recently added an option for the PARDISO MKL.

My personal feeling is to incorporate the SPOOLES solver for the time being and continue to investigate other solvers (and keep on eye on what CalculiX is doing). The SPOOLES solver has been around for a while and including it as an option would not be a disadvantage (even if we later add other sparse solver options). If anyone is interested in looking into this, go ahead and create a thread about it.

Brian Esp

For small DOF problems, this card "PARAM, SOLLIB, ZZPACK" can be used and is reliable (banded solver). However, for larger DOF programs, a sparse solver may be required. MYSTRAN currently uses an older Intel solver for this case (this only exists for the complied EXE but ***NOT*** for the files on GitHub, which is a known issue). However, this older sparse solver is not very reliable. This challenge has increased in priority because we can not use the older Intel MKL solver that Bill used in the past (so MYSTRAN only has the banded solvers LAPACK/ARPACK).

We are investigating various sparse solvers. We previously looked at BCSLIB-EXT, but the cost is relatively high and it appears there may be other solvers that are just as good (if not better).

1. The SPOOLES solver is an option, but it seems to be relatively slow compared to other options.

2. PARDSIO with Intel MKL is an option, but requires an Intel compiler and the user must also download the Intel MKL (personal information is required).

3. PARDISO 6 is more improved than PARDISO MKL, but requires the user download a free license every year (personal information is required).

4. PaStiX may be the best option since it is modern and free. We can take a page from CalculiX and see how their investigation is going since they looking at other solvers.

CalculiX has historically used SPOOLES, but recently added an option for the PARDISO MKL.

My personal feeling is to incorporate the SPOOLES solver for the time being and continue to investigate other solvers (and keep on eye on what CalculiX is doing). The SPOOLES solver has been around for a while and including it as an option would not be a disadvantage (even if we later add other sparse solver options). If anyone is interested in looking into this, go ahead and create a thread about it.

Brian Esp