Visible to Intel only — GUID: GUID-2CB6BB96-5197-451E-A572-FB3133764957
Visible to Intel only — GUID: GUID-2CB6BB96-5197-451E-A572-FB3133764957
?tfsm
Solves a matrix equation (one operand is a triangular matrix in RFP format).
Syntax
call stfsm(transr, side, uplo, trans, diag, m, n, alpha, a, b, ldb)
call dtfsm(transr, side, uplo, trans, diag, m, n, alpha, a, b, ldb)
call ctfsm(transr, side, uplo, trans, diag, m, n, alpha, a, b, ldb)
call ztfsm(transr, side, uplo, trans, diag, m, n, alpha, a, b, ldb)
Include Files
- mkl.fi
Description
The ?tfsm routines solve one of the following matrix equations:
op(A)*X = alpha*B,
or
X*op(A) = alpha*B,
where:
alpha is a scalar,
X and B are m-by-n matrices,
A is a unit, or non-unit, upper or lower triangular matrix in rectangular full packed (RFP) format.
op(A) can be one of the following:
op(A) = A or op(A) = AT for real flavors
op(A) = A or op(A) = AH for complex flavors
The matrix B is overwritten by the solution matrix X.
Input Parameters
- transr
-
CHARACTER*1.
if transr = 'N' or 'n', the normal form of RFP A is stored;
if transr = 'T' or 't', the transpose form of RFP A is stored;
if transr = 'C' or 'c', the conjugate-transpose form of RFP A is stored.
- side
-
CHARACTER*1. Specifies whether op(A) appears on the left or right of X in the equation:
if side = 'L' or 'l', then op(A)*X = alpha*B;
if side = 'R' or 'r', then X*op(A) = alpha*B.
- uplo
-
CHARACTER*1. Specifies whether the RFP matrix A is upper or lower triangular:
if uplo = 'U' or 'u', then the matrix is upper triangular;
if uplo = 'L' or 'l', then the matrix is low triangular.
- trans
-
CHARACTER*1. Specifies the form of op(A) used in the matrix multiplication:
if trans = 'N' or 'n', then op(A) = A;
if trans = 'T' or 't', then op(A) = A';
if trans = 'C' or 'c', then op(A) = conjg(A').
- diag
-
CHARACTER*1. Specifies whether the RFP matrix A is unit triangular:
if diag = 'U' or 'u' then the matrix is unit triangular;
if diag = 'N' or 'n', then the matrix is not unit triangular.
- m
-
INTEGER. Specifies the number of rows of B. The value of m must be at least zero.
- n
-
INTEGER. Specifies the number of columns of B. The value of n must be at least zero.
- alpha
-
REAL for stfsm
DOUBLE PRECISION for dtfsm
COMPLEX for ctfsm
DOUBLE COMPLEX for ztfsm
Specifies the scalar alpha.
When alpha is zero, then a is not referenced and b need not be set before entry.
- a
-
REAL for stfsm
DOUBLE PRECISION for dtfsm
COMPLEX for ctfsm
DOUBLE COMPLEX for ztfsm
Array, size (n*(n+1)/2). Contains the matrix A in RFP format.
- b
-
REAL for stfsm
DOUBLE PRECISION for dtfsm
COMPLEX for ctfsm
DOUBLE COMPLEX for ztfsm
Array, size (1, ldb*n)
Before entry, the leading m-by-n part of the array b must contain the right-hand side matrix B.
- ldb
-
INTEGER. Specifies the leading dimension of b as declared in the calling (sub)program. The value of ldb must be at least max(1, m).
Output Parameters
- b
-
Overwritten by the solution matrix X.