ctptrs.f man page

ctptrs.f —

Synopsis

Functions/Subroutines

subroutine ctptrs (UPLO, TRANS, DIAG, N, NRHS, AP, B, LDB, INFO)
CTPTRS

Function/Subroutine Documentation

subroutine ctptrs (characterUPLO, characterTRANS, characterDIAG, integerN, integerNRHS, complex, dimension( * )AP, complex, dimension( ldb, * )B, integerLDB, integerINFO)

CTPTRS

Purpose:

CTPTRS solves a triangular system of the form

   A * X = B,  A**T * X = B,  or  A**H * X = B,

where A is a triangular matrix of order N stored in packed format,
and B is an N-by-NRHS matrix.  A check is made to verify that A is
nonsingular.

Parameters:

UPLO

UPLO is CHARACTER*1
= 'U':  A is upper triangular;
= 'L':  A is lower triangular.

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)

DIAG

DIAG is CHARACTER*1
= 'N':  A is non-unit triangular;
= 'U':  A is 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 matrix 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(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
if UPLO = 'L', AP(i + (j-1)*(2*n-j)/2) = A(i,j) for j<=i<=n.

B

B is COMPLEX array, dimension (LDB,NRHS)
On entry, the right hand side matrix B.
On exit, if INFO = 0, the solution matrix X.

LDB

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

INFO

INFO is INTEGER
= 0:  successful exit
< 0:  if INFO = -i, the i-th argument had an illegal value
> 0:  if INFO = i, the i-th diagonal element of A is zero,
      indicating that the matrix is singular and the
      solutions X have not been computed.

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

November 2011

Definition at line 131 of file ctptrs.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

ctptrs(3) is an alias of ctptrs.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK