ZTRSYL3 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.


  This is the block version of the algorithm.

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.

SWORK

          SWORK is DOUBLE PRECISION array, dimension (MAX(2, ROWS),


          MAX(1,COLS)).


          On exit, if INFO = 0, SWORK(1) returns the optimal value ROWS


          and SWORK(2) returns the optimal COLS.

LDSWORK

          LDSWORK is INTEGER


          LDSWORK >= MAX(2,ROWS), where ROWS = ((M + NB - 1) / NB + 1)


          and NB is the optimal block size.


          If LDSWORK = -1, then a workspace query is assumed; the routine


          only calculates the optimal dimensions of the SWORK matrix,


          returns these values as the first and second entry of the SWORK


          matrix, and no error message related LWORK is issued by XERBLA.

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).