ztrsyl (3) - Linux Manuals

NAME

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.

Pages related to ztrsyl