zgbt02.f - Man Page

TESTING/LIN/zgbt02.f

Synopsis

Functions/Subroutines

subroutine zgbt02 (trans, m, n, kl, ku, nrhs, a, lda, x, ldx, b, ldb, rwork, resid)
ZGBT02

Function/Subroutine Documentation

subroutine zgbt02 (character trans, integer m, integer n, integer kl, integer ku, integer nrhs, complex*16, dimension( lda, * ) a, integer lda, complex*16, dimension( ldx, * ) x, integer ldx, complex*16, dimension( ldb, * ) b, integer ldb, double precision, dimension( * ) rwork, double precision resid)

ZGBT02

Purpose:

``` ZGBT02 computes the residual for a solution of a banded system of
equations op(A)*X = B:
RESID = norm(B - op(A)*X) / ( norm(op(A)) * norm(X) * EPS ),
where op(A) = A, A**T, or A**H, depending on TRANS, and EPS is the
machine epsilon.```
Parameters

TRANS

```          TRANS is CHARACTER*1
Specifies the form of the system of equations:
= 'N':  A    * X = B  (No transpose)
= 'T':  A**T * X = B  (Transpose)
= 'C':  A**H * X = B  (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
The number of subdiagonals within the band of A.  KL >= 0.```

KU

```          KU is INTEGER
The number of superdiagonals within the band of A.  KU >= 0.```

NRHS

```          NRHS is INTEGER
The number of columns of B.  NRHS >= 0.```

A

```          A is COMPLEX*16 array, dimension (LDA,N)
The original matrix A in band storage, stored in rows 1 to
KL+KU+1.```

LDA

```          LDA is INTEGER
The leading dimension of the array A.  LDA >= max(1,KL+KU+1).```

X

```          X is COMPLEX*16 array, dimension (LDX,NRHS)
The computed solution vectors for the system of linear
equations.```

LDX

```          LDX is INTEGER
The leading dimension of the array X.  If TRANS = 'N',
LDX >= max(1,N); if TRANS = 'T' or 'C', LDX >= max(1,M).```

B

```          B is COMPLEX*16 array, dimension (LDB,NRHS)
On entry, the right hand side vectors for the system of
linear equations.
On exit, B is overwritten with the difference B - A*X.```

LDB

```          LDB is INTEGER
The leading dimension of the array B.  IF TRANS = 'N',
LDB >= max(1,M); if TRANS = 'T' or 'C', LDB >= max(1,N).```

RWORK

```          RWORK is DOUBLE PRECISION array, dimension (MAX(1,LRWORK)),
where LRWORK >= M when TRANS = 'T' or 'C'; otherwise, RWORK
is not referenced.```

RESID

```          RESID is DOUBLE PRECISION
The maximum over the number of right hand sides of
norm(B - op(A)*X) / ( norm(op(A)) * norm(X) * EPS ).```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 146 of file zgbt02.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page zgbt02(3) is an alias of zgbt02.f(3).

Tue Nov 28 2023 12:08:43 Version 3.12.0 LAPACK