## Developer Reference

• 2020.2
• 07/15/2020
• Public Content
Contents

# p?potri

Computes the inverse of a symmetric/Hermitian positive definite distributed matrix.

## Syntax

Include Files
Description
The
p?potri
routine
computes the inverse of a real symmetric or complex Hermitian positive definite distributed matrix sub(
A
) =
A
(
ia
:
ia
+
n
-1,
ja
:
ja
+
n
-1) using the Cholesky factorization sub(
A
) =
U
H
*U
or sub(
A
) =
L*L
H
computed by
p?potrf
.
Input Parameters
uplo
(global)
CHARACTER*1
.
Must be
'U'
or
'L'
.
Specifies whether the upper or lower triangular part of the symmetric/Hermitian matrix sub(
A
) is stored.
If
uplo
=
'U'
, upper triangle of sub(
A
) is stored. If
uplo
=
'L'
, lower triangle of sub(
A
) is stored.
n
(global)
INTEGER
.
The number of rows and columns to be operated on, that is, the order of the distributed matrix sub(
A
)
(
n
0)
.
a
(local)
REAL
for
pspotri
DOUBLE PRECISION
for
pdpotri
COMPLEX
for
pcpotri
DOUBLE COMPLEX
for
pzpotri
.
Pointer into the local memory to an array of local size
(
lld_a
,
LOCc
(
ja
+
n
-1))
.
On entry, the array
a
contains the local pieces of the triangular factor
U
or
L
from the Cholesky factorization sub(
A
) =
U
H
*U,
or sub(
A
) =
L*L
H
, as computed by
p?potrf
.
ia
,
ja
(global)
INTEGER
.
The row and column indices in the global matrix
A
indicating the first row and the first column of the matrix sub(
A
), respectively.
desca
(global and local)
INTEGER
array of size
dlen_
. The array descriptor for the distributed matrix
A
.
Output Parameters
a
On exit, overwritten by the local pieces of the upper or lower triangle of the (symmetric/Hermitian) inverse of sub(
A
).
info
(global)
INTEGER
.
If