p?lauum
p?lauum
Computes the product or , where
U
*U
' L
'*L
U
and L
are upper or lower triangular matrices.Syntax
void
pslauum
(
char
*uplo
,
MKL_INT
*n
,
float
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
);
void
pdlauum
(
char
*uplo
,
MKL_INT
*n
,
double
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
);
void
pclauum
(
char
*uplo
,
MKL_INT
*n
,
MKL_Complex8
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
);
void
pzlauum
(
char
*uplo
,
MKL_INT
*n
,
MKL_Complex16
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
);
Include Files
- mkl_scalapack.h
Description
The
p?lauum
function
computes the product U*U
' or L'*L
, where the triangular factor U
or L
is stored in the upper or lower triangular part of the matrix sub(
.A
)= A
(ia
:ia
+n
-1, ja
:ja
+n
-1)If
uplo
= 'U'
or 'u'
, then the upper triangle of the result is stored, overwriting the factor U
in sub(A
). If uplo
= 'L'
or 'l'
, then the lower triangle of the result is stored, overwriting the factor L
in sub(A
). This is the blocked form of the algorithm, calling Level 3 PBLAS.
Input Parameters
- uplo
- (global)Specifies whether the triangular factor stored in the matrix sub(A) is upper or lower triangular:='U': upper triangular='L': lower triangular.
- n
- (global)The number of rows and columns to be operated on, that is, the order of the triangular factorUorL..n≥0
- a
- (local)Pointer into the local memory to an array of size. On entry, the local pieces of the triangular factorlld_a*LOCc(ja+n-1)UorL.
- ia
- (global)The row index in the global matrixAindicating the first row of sub(A).
- ja
- (global)The column index in the global matrixAindicating the first column of sub(A).
- desca
- (global and local) array of sizedlen_. The array descriptor for the distributed matrixA.
Output Parameters
- a
- (local)On exit, if, the upper triangle of the distributed matrix sub(uplo='U'A) is overwritten with the upper triangle of the productU*U' ; if, the lower triangle of sub(uplo='L'A) is overwritten with the lower triangle of the product.L'*L