redhat man page for slaqsp

SLAQSP(l)								 )								 SLAQSP(l)

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

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

	   CHARACTER	  EQUED, UPLO

	   INTEGER	  N

	   REAL 	  AMAX, SCOND

	   REAL 	  AP( * ), S( * )

PURPOSE
       SLAQSP 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) REAL 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) REAL array, dimension (N)
	       The scale factors for A.

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

       AMAX    (input) REAL
	       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	       = 'Y':  Equilibration was done, i.e., A has been replaced by diag(S) * A * diag(S).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 							 SLAQSP(l)