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CPPSV(3F)							     CPPSV(3F)

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

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

	 CHARACTER     UPLO

	 INTEGER       INFO, LDB, N, NRHS

	 COMPLEX       AP( * ), B( LDB, * )

PURPOSE
     CPPSV computes the solution to a complex system of linear equations
	A * X = B, where A is an N-by-N Hermitian positive definite matrix
     stored in packed format 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.

     AP	     (input/output) COMPLEX array, dimension (N*(N+1)/2)
	     On entry, the upper or lower triangle of the Hermitian matrix A,
	     packed columnwise in a linear array.  The j-th column of A is
	     stored in the array AP as follows:	 if UPLO = 'U', AP(i + (j-
	     1)*j/2) = A(i,j) for 1<=i<=j; if UPLO = 'L', AP(i + (j-1)*(2n-
	     j)/2) = A(i,j) for j<=i<=n.  See below for further details.

	     On exit, if INFO = 0, the factor U or L from the Cholesky
	     factorization A = U**H*U or A = L*L**H, in the same storage
	     format as A.

									Page 1

CPPSV(3F)							     CPPSV(3F)

     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.

FURTHER DETAILS
     The packed storage scheme is illustrated by the following example when N
     = 4, UPLO = 'U':

     Two-dimensional storage of the Hermitian matrix A:

	a11 a12 a13 a14
	    a22 a23 a24
		a33 a34	    (aij = conjg(aji))
		    a44

     Packed storage of the upper triangle of A:

     AP = [ a11, a12, a22, a13, a23, a33, a14, a24, a34, a44 ]

									Page 2

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