CXML
        	    
LAPACK version 3.0
cposv(3)

PURPOSE
  CPOSV - compute the solution to a complex system of linear equations A * X
  = B,

SYNTAX
  SUBROUTINE CPOSV( UPLO, N, NRHS, A, LDA, B, LDB, INFO )

      CHARACTER	    UPLO

      INTEGER	    INFO, LDA, LDB, N, NRHS

      COMPLEX	    A( LDA, * ), B( LDB, * )

DESCRIPTION
  CPOSV computes the solution to a complex system of linear equations A * X =
  B, where A is an N-by-N Hermitian positive definite matrix and X and B are
  N-by-NRHS matrices.

  The Cholesky decomposition is used to factor A as
     A = U**H* U,  if UPLO = 'U', or
     A = L * L**H,  if UPLO = 'L',
  where U is an upper triangular matrix and  L is a lower triangular matrix.
  The factored form of A is then used to solve the system of equations A * X
  = B.

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

  N	  (input) INTEGER
	  The number of linear equations, i.e., the order of the matrix A.  N
	  >= 0.

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

  A	  (input/output) COMPLEX array, dimension (LDA,N)
	  On entry, the Hermitian matrix A.  If UPLO = 'U', the leading N-
	  by-N upper triangular part of A contains the upper triangular part
	  of the matrix A, and the strictly lower triangular part of A is not
	  referenced.  If UPLO = 'L', the leading N-by-N lower triangular
	  part of A contains the lower triangular part of the matrix A, and
	  the strictly upper triangular part of A is not referenced.

	  On exit, if INFO = 0, the factor U or L from the Cholesky
	  factorization A = U**H*U or A = L*L**H.

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

  B	  (input/output) COMPLEX array, dimension (LDB,NRHS)
	  On entry, the N-by-NRHS right hand side matrix B.  On exit, if INFO
	  = 0, the N-by-NRHS solution matrix X.

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

  INFO	  (output) INTEGER
	  = 0:	successful exit
	  < 0:	if INFO = -i, the i-th argument had an illegal value
	  > 0:	if INFO = i, the leading minor of order i of A is not
	  positive definite, so the factorization could not be completed, and
	  the solution has not been computed.