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



NAME
       DPOTRS

SYNOPSIS
       SUBROUTINE DPOTRS (UPLO, N, NRHS, A, LDA, B, LDB, INFO)



PURPOSE
            DPOTRS solves a system of linear equations A*X = B with a symmetric
            positive definite matrix A using the Cholesky factorization
            A = U**T*U or A = L*L**T computed by DPOTRF.




ARGUMENTS
           UPLO      (input)
                     UPLO is CHARACTER*1
                     = 'U':  Upper triangle of A is stored;
                     = 'L':  Lower triangle of A is stored.

           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 DOUBLE PRECISION array, dimension (LDA,N)
                     The triangular factor U or L from the Cholesky factorization
                     A = U**T*U or A = L*L**T, as computed by DPOTRF.

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

           B         (input/output)
                     B is DOUBLE PRECISION 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                      DPOTRS(3)