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



NAME
       CHPTRS

SYNOPSIS
       SUBROUTINE CHPTRS (UPLO, N, NRHS, AP, IPIV, B, LDB, INFO)



PURPOSE
            CHPTRS solves a system of linear equations A*X = B with a complex
            Hermitian matrix A stored in packed format using the factorization
            A = U*D*U**H or A = L*D*L**H computed by CHPTRF.




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.

           AP        (input)
                     AP is COMPLEX array, dimension (N*(N+1)/2)
                     The block diagonal matrix D and the multipliers used to
                     obtain the factor U or L as computed by CHPTRF, stored as a
                     packed triangular matrix.

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

           B         (input/output)
                     B is COMPLEX 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).

           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                      CHPTRS(3)