ZHETRS2(3)     LAPACK routine of NEC Numeric Library Collection     ZHETRS2(3)



NAME
       ZHETRS2

SYNOPSIS
       SUBROUTINE ZHETRS2 (UPLO, N, NRHS, A, LDA, IPIV, B, LDB, WORK, INFO)



PURPOSE
            ZHETRS2 solves a system of linear equations A*X = B with a complex
            Hermitian matrix A using the factorization A = U*D*U**H or
            A = L*D*L**H computed by ZHETRF and converted by ZSYCONV.




ARGUMENTS
           UPLO      (input)
                     UPLO is CHARACTER*1
                     Specifies whether the details of the factorization are stored
                     as an upper or lower triangular matrix.
                     = 'U':  Upper triangular, form is A = U*D*U**H;
                     = 'L':  Lower triangular, form is A = L*D*L**H.

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

           NRHS      (input)
                     NRHS is INTEGER
                     The number of right hand sides, i.e., the number of columns
                     of the matrix B.  NRHS >= 0.

           A         (input)
                     A is COMPLEX*16 array, dimension (LDA,N)
                     The block diagonal matrix D and the multipliers used to
                     obtain the factor U or L as computed by ZHETRF.

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

           IPIV      (input)
                     IPIV is INTEGER array, dimension (N)
                     Details of the interchanges and the block structure of D
                     as determined by ZHETRF.

           B         (input/output)
                     B is COMPLEX*16 array, dimension (LDB,NRHS)
                     On entry, the right hand side matrix B.
                     On exit, the solution matrix X.

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

           WORK      (output)
                     WORK is REAL array, dimension (N)

           INFO      (output)
                     INFO is INTEGER
                     = 0:  successful exit
                     < 0:  if INFO = -i, the i-th argument had an illegal value



LAPACK routine                  31 October 2017                     ZHETRS2(3)