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/home/abuild/rpmbuild/BUILD/lapack-3.12.0/TESTING/LIN/ctpt03.f(3) Library Functions Manual /home/abuild/rpmbuild/BUILD/lapack-3.12.0/TESTING/LIN/ctpt03.f(3)

NAME

/home/abuild/rpmbuild/BUILD/lapack-3.12.0/TESTING/LIN/ctpt03.f

SYNOPSIS

Functions/Subroutines


subroutine CTPT03 (uplo, trans, diag, n, nrhs, ap, scale, cnorm, tscal, x, ldx, b, ldb, work, resid)
CTPT03

Function/Subroutine Documentation

subroutine CTPT03 (character uplo, character trans, character diag, integer n, integer nrhs, complex, dimension( * ) ap, real scale, real, dimension( * ) cnorm, real tscal, complex, dimension( ldx, * ) x, integer ldx, complex, dimension( ldb, * ) b, integer ldb, complex, dimension( * ) work, real resid)

CTPT03

Purpose:

!>
!> CTPT03 computes the residual for the solution to a scaled triangular
!> system of equations A*x = s*b,  A**T *x = s*b,  or  A**H *x = s*b,
!> when the triangular matrix A is stored in packed format.  Here A**T
!> denotes the transpose of A, A**H denotes the conjugate transpose of
!> A, s is a scalar, and x and b are N by NRHS matrices.  The test ratio
!> is the maximum over the number of right hand sides of
!>    norm(s*b - op(A)*x) / ( norm(op(A)) * norm(x) * EPS ),
!> where op(A) denotes A, A**T, or A**H, and EPS is the machine epsilon.
!> 

Parameters

UPLO

!>          UPLO is CHARACTER*1
!>          Specifies whether the matrix A is upper or lower triangular.
!>          = 'U':  Upper triangular
!>          = 'L':  Lower triangular
!> 

TRANS

!>          TRANS is CHARACTER*1
!>          Specifies the operation applied to A.
!>          = 'N':  A *x = s*b     (No transpose)
!>          = 'T':  A**T *x = s*b  (Transpose)
!>          = 'C':  A**H *x = s*b  (Conjugate transpose)
!> 

DIAG

!>          DIAG is CHARACTER*1
!>          Specifies whether or not the matrix A is unit triangular.
!>          = 'N':  Non-unit triangular
!>          = 'U':  Unit triangular
!> 

N

!>          N is INTEGER
!>          The order of the matrix A.  N >= 0.
!> 

NRHS

!>          NRHS is INTEGER
!>          The number of right hand sides, i.e., the number of columns
!>          of the matrices X and B.  NRHS >= 0.
!> 

AP

!>          AP is COMPLEX array, dimension (N*(N+1)/2)
!>          The upper or lower triangular matrix A, packed columnwise in
!>          a linear array.  The j-th column of A is stored in the array
!>          AP as follows:
!>          if UPLO = 'U', AP((j-1)*j/2 + i) = A(i,j) for 1<=i<=j;
!>          if UPLO = 'L',
!>             AP((j-1)*(n-j) + j*(j+1)/2 + i-j) = A(i,j) for j<=i<=n.
!> 

SCALE

!>          SCALE is REAL
!>          The scaling factor s used in solving the triangular system.
!> 

CNORM

!>          CNORM is REAL array, dimension (N)
!>          The 1-norms of the columns of A, not counting the diagonal.
!> 

TSCAL

!>          TSCAL is REAL
!>          The scaling factor used in computing the 1-norms in CNORM.
!>          CNORM actually contains the column norms of TSCAL*A.
!> 

X

!>          X is COMPLEX 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.  LDX >= max(1,N).
!> 

B

!>          B is COMPLEX array, dimension (LDB,NRHS)
!>          The right hand side vectors for the system of linear
!>          equations.
!> 

LDB

!>          LDB is INTEGER
!>          The leading dimension of the array B.  LDB >= max(1,N).
!> 

WORK

!>          WORK is COMPLEX array, dimension (N)
!> 

RESID

!>          RESID is REAL
!>          The maximum over the number of right hand sides of
!>          norm(op(A)*x - s*b) / ( norm(op(A)) * norm(x) * EPS ).
!> 

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 160 of file ctpt03.f.

Author

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Version 3.12.0 LAPACK