csyconvf.f man page

csyconvf.f

Synopsis

Functions/Subroutines

subroutine csyconvf (UPLO, WAY, N, A, LDA, E, IPIV, INFO)
CSYCONVF

Function/Subroutine Documentation

subroutine csyconvf (character UPLO, character WAY, integer N, complex, dimension( lda, * ) A, integer LDA, complex, dimension( * ) E, integer, dimension( * ) IPIV, integer INFO)

CSYCONVF

Purpose:

If parameter WAY = 'C':
CSYCONVF converts the factorization output format used in
CSYTRF provided on entry in parameter A into the factorization
output format used in CSYTRF_RK (or CSYTRF_BK) that is stored
on exit in parameters A and E. It also coverts in place details of
the intechanges stored in IPIV from the format used in CSYTRF into
the format used in CSYTRF_RK (or CSYTRF_BK).

If parameter WAY = 'R':
CSYCONVF performs the conversion in reverse direction, i.e.
converts the factorization output format used in CSYTRF_RK
(or CSYTRF_BK) provided on entry in parameters A and E into
the factorization output format used in CSYTRF that is stored
on exit in parameter A. It also coverts in place details of
the intechanges stored in IPIV from the format used in CSYTRF_RK
(or CSYTRF_BK) into the format used in CSYTRF.

CSYCONVF can also convert in Hermitian matrix case, i.e. between
formats used in CHETRF and CHETRF_RK (or CHETRF_BK).
Parameters:

UPLO

UPLO is CHARACTER*1
Specifies whether the details of the factorization are
stored as an upper or lower triangular matrix A.
= 'U':  Upper triangular
= 'L':  Lower triangular

WAY

WAY is CHARACTER*1
= 'C': Convert
= 'R': Revert

N

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

A

A is COMPLEX array, dimension (LDA,N)

1) If WAY ='C':

On entry, contains factorization details in format used in
CSYTRF:
a) all elements of the symmetric block diagonal
matrix D on the diagonal of A and on superdiagonal
(or subdiagonal) of A, and
b) If UPLO = 'U': multipliers used to obtain factor U
in the superdiagonal part of A.
If UPLO = 'L': multipliers used to obtain factor L
in the superdiagonal part of A.

On exit, contains factorization details in format used in
CSYTRF_RK or CSYTRF_BK:
a) ONLY diagonal elements of the symmetric block diagonal
matrix D on the diagonal of A, i.e. D(k,k) = A(k,k);
(superdiagonal (or subdiagonal) elements of D
are stored on exit in array E), and
b) If UPLO = 'U': factor U in the superdiagonal part of A.
If UPLO = 'L': factor L in the subdiagonal part of A.

2) If WAY = 'R':

On entry, contains factorization details in format used in
CSYTRF_RK or CSYTRF_BK:
a) ONLY diagonal elements of the symmetric block diagonal
matrix D on the diagonal of A, i.e. D(k,k) = A(k,k);
(superdiagonal (or subdiagonal) elements of D
are stored on exit in array E), and
b) If UPLO = 'U': factor U in the superdiagonal part of A.
If UPLO = 'L': factor L in the subdiagonal part of A.

On exit, contains factorization details in format used in
CSYTRF:
a) all elements of the symmetric block diagonal
matrix D on the diagonal of A and on superdiagonal
(or subdiagonal) of A, and
b) If UPLO = 'U': multipliers used to obtain factor U
in the superdiagonal part of A.
If UPLO = 'L': multipliers used to obtain factor L
in the superdiagonal part of A.

LDA

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

E

E is COMPLEX array, dimension (N)

1) If WAY ='C':

On entry, just a workspace.

On exit, contains the superdiagonal (or subdiagonal)
elements of the symmetric block diagonal matrix D
with 1-by-1 or 2-by-2 diagonal blocks, where
If UPLO = 'U': E(i) = D(i-1,i), i=2:N, E(1) is set to 0;
If UPLO = 'L': E(i) = D(i+1,i), i=1:N-1, E(N) is set to 0.

2) If WAY = 'R':

On entry, contains the superdiagonal (or subdiagonal)
elements of the symmetric block diagonal matrix D
with 1-by-1 or 2-by-2 diagonal blocks, where
If UPLO = 'U': E(i) = D(i-1,i),i=2:N, E(1) not referenced;
If UPLO = 'L': E(i) = D(i+1,i),i=1:N-1, E(N) not referenced.

On exit, is not changed

IPIV

IPIV is INTEGER array, dimension (N)

1) If WAY ='C':
On entry, details of the interchanges and the block
structure of D in the format used in CSYTRF.
On exit, details of the interchanges and the block
structure of D in the format used in CSYTRF_RK
( or CSYTRF_BK).

1) If WAY ='R':
On entry, details of the interchanges and the block
structure of D in the format used in CSYTRF_RK
( or CSYTRF_BK).
On exit, details of the interchanges and the block
structure of D in the format used in CSYTRF.

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

Univ. of Colorado Denver

NAG Ltd.

Date:

November 2017

Contributors:

November 2017,  Igor Kozachenko,
Computer Science Division,
University of California, Berkeley

Definition at line 211 of file csyconvf.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

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

Tue Nov 14 2017 Version 3.8.0 LAPACK