clarhs.f - Man Page

TESTING/LIN/clarhs.f

Synopsis

Functions/Subroutines

subroutine clarhs (path, xtype, uplo, trans, m, n, kl, ku, nrhs, a, lda, x, ldx, b, ldb, iseed, info)
CLARHS

Function/Subroutine Documentation

subroutine clarhs (character*3 path, character xtype, character uplo, character trans, integer m, integer n, integer kl, integer ku, integer nrhs, complex, dimension( lda, * ) a, integer lda, complex, dimension( ldx, * ) x, integer ldx, complex, dimension( ldb, * ) b, integer ldb, integer, dimension( 4 ) iseed, integer info)

CLARHS

Purpose:

``` CLARHS 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, A**T, or A**H, depending on TRANS.```
Parameters

PATH

```          PATH is CHARACTER*3
The type of the complex matrix A.  PATH may be given in any
combination of upper and lower case.  Valid paths include
xGE:  General m x n matrix
xGB:  General banded matrix
xPO:  Hermitian positive definite, 2-D storage
xPP:  Hermitian positive definite packed
xPB:  Hermitian positive definite banded
xHE:  Hermitian indefinite, 2-D storage
xHP:  Hermitian indefinite packed
xHB:  Hermitian indefinite 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.```

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.```

UPLO

```          UPLO is CHARACTER*1
Used only if A is symmetric or triangular; specifies whether
the upper or lower triangular part of the matrix A is stored.
= 'U':  Upper triangular
= 'L':  Lower triangular```

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)```

M

```          M is INTEGER
The number of rows of the matrix A.  M >= 0.```

N

```          N is INTEGER
The number of columns of the matrix A.  N >= 0.```

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.```

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```

NRHS

```          NRHS is INTEGER
The number of right hand side vectors in the system A*X = B.```

A

```          A is COMPLEX array, dimension (LDA,N)
The test matrix whose type is given by PATH.```

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).```

X

```          X is or output) COMPLEX 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.```

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).```

B

```          B is COMPLEX 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.```

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).```

ISEED

```          ISEED is INTEGER array, dimension (4)
The seed vector for the random number generator (used in
CLATMS).  Modified on exit.```

INFO

```          INFO is INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 206 of file clarhs.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page clarhs(3) is an alias of clarhs.f(3).

Tue Nov 28 2023 12:08:42 Version 3.12.0 LAPACK