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dppsv.f(3)				      LAPACK				       dppsv.f(3)

NAME
       dppsv.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dppsv (UPLO, N, NRHS, AP, B, LDB, INFO)
	    DPPSV computes the solution to system of linear equations A * X = B for OTHER
	   matrices

Function/Subroutine Documentation
   subroutine dppsv (characterUPLO, integerN, integerNRHS, double precision, dimension( * )AP,
       double precision, dimension( ldb, * )B, integerLDB, integerINFO)
	DPPSV computes the solution to system of linear equations A * X = B for OTHER matrices

       Purpose:

	    DPPSV computes the solution to a real system of linear equations
	       A * X = B,
	    where A is an N-by-N symmetric 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**T* U,  if UPLO = 'U', or
	       A = L * L**T,  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.

       Parameters:
	   UPLO

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

	   N

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

	   NRHS

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

	   AP

		     AP is DOUBLE PRECISION array, dimension (N*(N+1)/2)
		     On entry, the upper or lower triangle of the symmetric 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**T*U or A = L*L**T, in the same storage
		     format as A.

	   B

		     B is DOUBLE PRECISION 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

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

	   INFO

		     INFO is 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.

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   November 2011

       Further Details:

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

	     Two-dimensional storage of the symmetric 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 ]

       Definition at line 145 of file dppsv.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2				 Tue Sep 25 2012			       dppsv.f(3)
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