ztrsyl.f man page

ztrsyl.f —

Synopsis

Functions/Subroutines

subroutine ztrsyl (TRANA, TRANB, ISGN, M, N, A, LDA, B, LDB, C, LDC, SCALE, INFO)
ZTRSYL

Function/Subroutine Documentation

subroutine ztrsyl (characterTRANA, characterTRANB, integerISGN, integerM, integerN, complex*16, dimension( lda, * )A, integerLDA, complex*16, dimension( ldb, * )B, integerLDB, complex*16, dimension( ldc, * )C, integerLDC, double precisionSCALE, integerINFO)

ZTRSYL

Purpose:

ZTRSYL solves the complex Sylvester matrix equation:

   op(A)*X + X*op(B) = scale*C or
   op(A)*X - X*op(B) = scale*C,

where op(A) = A or A**H, and A and B are both upper triangular. A is
M-by-M and B is N-by-N; the right hand side C and the solution X are
M-by-N; and scale is an output scale factor, set <= 1 to avoid
overflow in X.

Parameters:

TRANA

TRANA is CHARACTER*1
Specifies the option op(A):
= 'N': op(A) = A    (No transpose)
= 'C': op(A) = A**H (Conjugate transpose)

TRANB

TRANB is CHARACTER*1
Specifies the option op(B):
= 'N': op(B) = B    (No transpose)
= 'C': op(B) = B**H (Conjugate transpose)

ISGN

ISGN is INTEGER
Specifies the sign in the equation:
= +1: solve op(A)*X + X*op(B) = scale*C
= -1: solve op(A)*X - X*op(B) = scale*C

M

M is INTEGER
The order of the matrix A, and the number of rows in the
matrices X and C. M >= 0.

N

N is INTEGER
The order of the matrix B, and the number of columns in the
matrices X and C. N >= 0.

A

A is COMPLEX*16 array, dimension (LDA,M)
The upper triangular matrix A.

LDA

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

B

B is COMPLEX*16 array, dimension (LDB,N)
The upper triangular matrix B.

LDB

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

C

C is COMPLEX*16 array, dimension (LDC,N)
On entry, the M-by-N right hand side matrix C.
On exit, C is overwritten by the solution matrix X.

LDC

LDC is INTEGER
The leading dimension of the array C. LDC >= max(1,M)

SCALE

SCALE is DOUBLE PRECISION
The scale factor, scale, set <= 1 to avoid overflow in X.

INFO

INFO is INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
= 1: A and B have common or very close eigenvalues; perturbed
     values were used to solve the equation (but the matrices
     A and B are unchanged).

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

November 2011

Definition at line 157 of file ztrsyl.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

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

Sat Nov 16 2013 Version 3.4.2 LAPACK