p?trmv
p?trmv
Computes a distributed matrix-vector product using a triangular matrix.
Syntax
void pstrmv
(
const char
*uplo
,
const char
*trans
,
const char
*diag
,
const MKL_INT
*n
,
const float
*a
,
const MKL_INT
*ia
,
const MKL_INT
*ja
,
const MKL_INT
*desca
,
float
*x
,
const MKL_INT
*ix
,
const MKL_INT
*jx
,
const MKL_INT
*descx
,
const MKL_INT
*incx
);
void pdtrmv
(
const char
*uplo
,
const char
*trans
,
const char
*diag
,
const MKL_INT
*n
,
const double
*a
,
const MKL_INT
*ia
,
const MKL_INT
*ja
,
const MKL_INT
*desca
,
double
*x
,
const MKL_INT
*ix
,
const MKL_INT
*jx
,
const MKL_INT
*descx
,
const MKL_INT
*incx
);
void pctrmv
(
const char
*uplo
,
const char
*trans
,
const char
*diag
,
const MKL_INT
*n
,
const MKL_Complex8
*a
,
const MKL_INT
*ia
,
const MKL_INT
*ja
,
const MKL_INT
*desca
,
MKL_Complex8
*x
,
const MKL_INT
*ix
,
const MKL_INT
*jx
,
const MKL_INT
*descx
,
const MKL_INT
*incx
);
void pztrmv
(
const char
*uplo
,
const char
*trans
,
const char
*diag
,
const MKL_INT
*n
,
const MKL_Complex16
*a
,
const MKL_INT
*ia
,
const MKL_INT
*ja
,
const MKL_INT
*desca
,
MKL_Complex16
*x
,
const MKL_INT
*ix
,
const MKL_INT
*jx
,
const MKL_INT
*descx
,
const MKL_INT
*incx
);
Include Files
- mkl_pblas.h
Description
The
p?trmv
routines perform one of the following distributed matrix-vector operations defined assub(
, or x
) := sub(A
)*sub(x
)sub(
, or x
) :=sub( A
)'*sub(x
)sub(
,x
) := conjg(sub(A
)')*sub(x
)where:
sub(
is a A
)n
-by-n
unit, or non-unit, upper or lower triangular distributed matrix,
sub(
,A
) = A
(ia
:ia
+n
-1, ja
:ja
+n
-1)sub(
is an x
)n
-element distributed vector.sub(
denotes x
)X
(ix
, jx
:jx
+n
-1)incx
= m_x
X
(ix
: ix
+n
-1, jx
)incx
= 1,Input Parameters
- uplo
- (global) Specifies whether the distributed matrixsub(is upper or lower triangular:A)iforuplo='U''u', then the matrix is upper triangular;iforuplo='L''l', then the matrix is low triangular.
- trans
- (global) Specifies the form ofop(sub(used in the matrix equation:A))ifortransa= 'N'', thenn'sub(;x) := sub(A)*sub(x)ifortransa= 'T'', thent'sub(;x) :=sub(A)'*sub(x)ifortransa= 'C'', thenc'sub(.x) := conjg(sub(A)')*sub(x)
- diag
- (global) Specifies whether the matrixsub(is unit triangular:A)ifordiag='U''u'then the matrix is unit triangular;ifordiag='N''n', then the matrix is not unit triangular.
- n
- (global) Specifies the order of the distributed matrixsub(,A)n≥0.
- a
- (local)Array, size at least(.lld_a, LOCq(1,ja+n-1))Before entry withoruplo='U''u', this array contains the local entries corresponding to the entries of the upper triangular distributed matrixsub(, and the local entries corresponding to the entries of the strictly lower triangular part of the distributed matrixA)sub(is not referenced.A)Before entry withoruplo='L''l', this array contains the local entries corresponding to the entries of the lower triangular distributed matrixsub(, and the local entries corresponding to the entries of the strictly upper triangular part of the distributed matrixA)sub(is not referenced .A)Whenordiag='U''u', the local entries corresponding to the diagonal elements of the submatrixsub(are not referenced either, but are assumed to be unity.A)
- ia,ja
- (global) The row and column indices in the distributed matrixAindicating the first row and the first column of the submatrixsub(, respectively.A)
- desca
- (global and local) array of dimension 9. The array descriptor of the distributed matrixA.
- x
- (local)Array, size at least(.jx-1)*m_x+ix+(n-1)*abs(incx))This array contains the entries of the distributed vectorsub(.x)
- ix,jx
- (global) The row and column indices in the distributed matrixXindicating the first row and the first column of the submatrixsub(, respectively.x)
- descx
- (global and local) array of dimension 9. The array descriptor of the distributed matrixX.
- incx
- (global) Specifies the increment for the elements ofsub(. Only two values are supported, namely 1 andx)m_x.incxmust not be zero.
Output Parameters
- x
- Overwritten by the transformed distributed vectorsub(.x)