Developer Reference for Intel® oneAPI Math Kernel Library for Fortran
descinit
Initializes the array descriptor for distributed matrix.
Syntax
call descinit( desc, m, n, mb, nb, irsrc, icsrc, ictxt, lld, info )
Description
descint The descint routine function initializes the array descriptor for distributed matrix.
Input Parameters
desc
(global) INTEGER . array of dimension DLEN_. The array descriptor of a distributed matrix to be set.
m
(global input) INTEGER . The number of rows in the distributed matrix. M >=0.
n
(global input) INTEGER . The number of columns in the distributed matrix. N >=0.
mb
(global input) INTEGER . The blocking factor used to distribute the rows of the matrix. MB >= 1.
nb
(global input) INTEGER . INTEGER . The blocking factor used to distribute the columns of the matrix. NB >= 1.
lrsrc
(global input) INTEGER . The process row over which the first row of the matrix is distributed. 0 <= IRSRC < NPROW.
lcsrc
(global input) INTEGER . The process column over which the first column of the matrix is distributed. 0 <= ICSRC < NPCOL.
ictxt
(global input) INTEGER . The BLACS context handle, indicating the global context of the operation on the matrix. The context itself is global.
lld
(local input) INTEGER . The leading dimension of the local array storing the local blocks of the distributed matrix. LLD >= MAX(1,LOCr(M)). LOCr() denotes the number of rows of a global dense matrix that the process in a grid receives after data distributing.
Output Parameters
info
(output) INTEGER .
= 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value