redhat man page for dlaqsp

DLAQSP(l)								 )								 DLAQSP(l)

NAME
       DLAQSP - equilibrate a symmetric matrix A using the scaling factors in the vector S

SYNOPSIS
       SUBROUTINE DLAQSP( UPLO, N, AP, S, SCOND, AMAX, EQUED )

	   CHARACTER	  EQUED, UPLO

	   INTEGER	  N

	   DOUBLE	  PRECISION AMAX, SCOND

	   DOUBLE	  PRECISION AP( * ), S( * )

PURPOSE
       DLAQSP equilibrates a symmetric matrix A using the scaling factors in the vector S.

ARGUMENTS
       UPLO    (input) CHARACTER*1
	       Specifies whether the upper or lower triangular part of the symmetric matrix A is stored.  = 'U':  Upper triangular
	       = 'L':  Lower triangular

       N       (input) INTEGER
	       The order of the matrix A.  N >= 0.

       AP      (input/output) 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.

	       On exit, the equilibrated matrix:  diag(S) * A * diag(S), in the same storage format as A.

       S       (input) DOUBLE PRECISION array, dimension (N)
	       The scale factors for A.

       SCOND   (input) DOUBLE PRECISION
	       Ratio of the smallest S(i) to the largest S(i).

       AMAX    (input) DOUBLE PRECISION
	       Absolute value of largest matrix entry.

       EQUED   (output) CHARACTER*1
	       Specifies whether or not equilibration was done.  = 'N':  No equilibration.
	       = 'Y':  Equilibration was done, i.e., A has been replaced by diag(S) * A * diag(S).

PARAMETERS
       THRESH is a threshold value used to decide if scaling should be done based on the ratio of the scaling factors.	If SCOND < THRESH, scaling
       is done.

       LARGE and SMALL are threshold values used to decide if scaling should be done based on the absolute size of the largest matrix element.	If
       AMAX > LARGE or AMAX < SMALL, scaling is done.

LAPACK version 3.0						   15 June 2000 							 DLAQSP(l)