LAPACK 3.12.0
LAPACK: Linear Algebra PACKage
|
subroutine slarhs | ( | character*3 | path, |
character | xtype, | ||
character | uplo, | ||
character | trans, | ||
integer | m, | ||
integer | n, | ||
integer | kl, | ||
integer | ku, | ||
integer | nrhs, | ||
real, dimension( lda, * ) | a, | ||
integer | lda, | ||
real, dimension( ldx, * ) | x, | ||
integer | ldx, | ||
real, dimension( ldb, * ) | b, | ||
integer | ldb, | ||
integer, dimension( 4 ) | iseed, | ||
integer | info | ||
) |
SLARHS
SLARHS chooses a set of NRHS random solution vectors and sets up the right hand sides for the linear system op(A) * X = B, where op(A) = A or A**T, depending on TRANS.
[in] | PATH | PATH is CHARACTER*3 The type of the real matrix A. PATH may be given in any combination of upper and lower case. Valid types include xGE: General m x n matrix xGB: General banded matrix xPO: Symmetric positive definite, 2-D storage xPP: Symmetric positive definite packed xPB: Symmetric positive definite banded xSY: Symmetric indefinite, 2-D storage xSP: Symmetric indefinite packed xSB: Symmetric indefinite banded xTR: Triangular xTP: Triangular packed xTB: Triangular banded xQR: General m x n matrix xLQ: General m x n matrix xQL: General m x n matrix xRQ: General m x n matrix where the leading character indicates the precision. |
[in] | XTYPE | XTYPE is CHARACTER*1 Specifies how the exact solution X will be determined: = 'N': New solution; generate a random X. = 'C': Computed; use value of X on entry. |
[in] | UPLO | UPLO is CHARACTER*1 Specifies whether the upper or lower triangular part of the matrix A is stored, if A is symmetric. = 'U': Upper triangular = 'L': Lower triangular |
[in] | TRANS | TRANS is CHARACTER*1 Used only if A is nonsymmetric; specifies the operation applied to the matrix A. = 'N': B := A * X (No transpose) = 'T': B := A**T * X (Transpose) = 'C': B := A**H * X (Conjugate transpose = Transpose) |
[in] | M | M is INTEGER The number or rows of the matrix A. M >= 0. |
[in] | N | N is INTEGER The number of columns of the matrix A. N >= 0. |
[in] | KL | KL is INTEGER Used only if A is a band matrix; specifies the number of subdiagonals of A if A is a general band matrix or if A is symmetric or triangular and UPLO = 'L'; specifies the number of superdiagonals of A if A is symmetric or triangular and UPLO = 'U'. 0 <= KL <= M-1. |
[in] | KU | KU is INTEGER Used only if A is a general band matrix or if A is triangular. If PATH = xGB, specifies the number of superdiagonals of A, and 0 <= KU <= N-1. If PATH = xTR, xTP, or xTB, specifies whether or not the matrix has unit diagonal: = 1: matrix has non-unit diagonal (default) = 2: matrix has unit diagonal |
[in] | NRHS | NRHS is INTEGER The number of right hand side vectors in the system A*X = B. |
[in] | A | A is REAL array, dimension (LDA,N) The test matrix whose type is given by PATH. |
[in] | LDA | LDA is INTEGER The leading dimension of the array A. If PATH = xGB, LDA >= KL+KU+1. If PATH = xPB, xSB, xHB, or xTB, LDA >= KL+1. Otherwise, LDA >= max(1,M). |
[in,out] | X | X is or output) REAL array, dimension(LDX,NRHS) On entry, if XTYPE = 'C' (for 'Computed'), then X contains the exact solution to the system of linear equations. On exit, if XTYPE = 'N' (for 'New'), then X is initialized with random values. |
[in] | LDX | LDX is INTEGER The leading dimension of the array X. If TRANS = 'N', LDX >= max(1,N); if TRANS = 'T', LDX >= max(1,M). |
[out] | B | B is REAL array, dimension (LDB,NRHS) The right hand side vector(s) for the system of equations, computed from B = op(A) * X, where op(A) is determined by TRANS. |
[in] | LDB | LDB is INTEGER The leading dimension of the array B. If TRANS = 'N', LDB >= max(1,M); if TRANS = 'T', LDB >= max(1,N). |
[in,out] | ISEED | ISEED is INTEGER array, dimension (4) The seed vector for the random number generator (used in SLATMS). Modified on exit. |
[out] | INFO | INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value |
Definition at line 203 of file slarhs.f.