To set and get BLACS array/object/whatever pointers needed in and from R. Because other packages has it's own memory stack vision that may not be visiable by this package or vice versa.
set.blacs.apts()get.blacs.apts()
The `set.blacs.apts()` is for advanced users. This one is needed to be called within R from `pbdBASE` package to set the pointers to the memory where BLACS had initialized so that the pointers are set to the right address of the memory stack.
The `get.blacs.apts()` is for debugging only. The advanced user mainly calls the C version `get_BLACS_APTS_from_R()` in `src/export_blacs/pkg_ools.c`.
I am lazy to use .C(), but should not hurt performance here. Eventually, .pbdBASEEnv should pass to .C() and set/get pointers from it instead of .GlobalEnv.