How to determine the matrix size of padded Hamiltonian (Padding Hamiltonian Matrix)

[tsuyoshi38]

When the code is available to treat the padded Hamiltonian matrix, we should set the good value for block_size_r (and block_size_c).

First,

1. Manually Given or Default Setting:

• Deafult setting for block_size_r and block_size_c should be given

• [ ] - block_size_r ~ 20 (suggested from our test calculations, though depends on hardware.)

• Is it okay to assume that block_size_r = block_size_c

• How to set proc_rows and proc_cols ?

• [ ] - we may be able to follow the present method.

• [ ] - But, see the constraints for ELPA shown below.

2. Constraints in Scalapack
3. Constraints in ELPA
   1. block_size_r = block_size_c
   2. proc_cols = M (integer) x proc_rows
   3. ?? needs more than 1 blocks in the corresponding column or row. ??