Parallel Engineering and Scientific Subroutine Library for AIX Version 2 Release 3: Guide and Reference

PADFREE--Deallocates Space for an Array Descriptor for a General Sparse Matrix

This sparse utility subroutine deallocates space that is used for the array descriptor for a global general sparse matrix A.

Syntax

On Entry

desc_a

is the array descriptor for the sparse matrix A.

Type: required

Specified as: the derived data type DESC_TYPE.

Notes and Coding Rules

1. Before you call this subroutine, you must have called PADALL.
2. You must deallocate b, x, sparse matrix A, and preconditioner data structure prcs before you deallocate the array descriptor desc_a.
3. PADALL allocates desc_a as necessary. Prior to further calls to PADALL with the same desc_a, you must call PADFREE; otherwise, there will be a memory leak.

Error Conditions

Computational Errors

None

Resource Errors

None.

Input-Argument and Miscellaneous Errors

Stage 1:  

1. desc_a has not been initialized.

Stage 2:  

1. The BLACS context is invalid.

Stage 3:  

1. This subroutine was called from outside the process grid.

Stage 4:  

1. The process grid is not np × 1.