Using Procs in translation
INTEGER W_RANK, . . .
CALL MPI_COMM_RANK(MPI_COMM_WORLD, W_RANK, ERRCODE)
. . .
IF (W_RANK < 4) THEN
BLK_START = W_RANK * BLK_SIZE
. . .
ENDIF
Procs1 p(4);
. . .
if (p.member()) {
blk_start = p.dim(0).crd() * blk_size;
. . .
}