Does anyone know if Lapack has the capability of solving Ax=b where the elements of A are themselves m by m matrices, and the elements of x and b are vectors of dimension m. I have not found anything that says that it can. Is there other public domain software that can do this efficiently?

I would greatly appreciate any help in this matter. Frank Muldoon

Allen Hindmarsh, at Lawrence Livermore National Lab, in Livermore, California, published a series of linear solvers in the '70s, including a block solver. If the reports are still available, they should be public domain. The Fortran listings are included.

Good luck!