CPOSV(l)	     LAPACK driver routine (version 1.1)	     CPOSV(l)

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

SYNOPSIS

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

      CHARACTER	    UPLO

      INTEGER	    INFO, LDA, LDB, N, NRHS

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

PURPOSE
  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 factori-
	  zation 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 posi-
	  tive definite, so the	factorization could not	be completed, and the
	  solution has not been	computed.


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