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NAME
     dlaqge - equilibrate a general M by N matrix A using the row
     and scaling factors in the vectors R and C

SYNOPSIS
     SUBROUTINE DLAQGE( M, N, A, LDA, R, C, ROWCND, COLCND, AMAX,
               EQUED )

     CHARACTER EQUED

     INTEGER LDA, M, N

     DOUBLE PRECISION AMAX, COLCND, ROWCND

     DOUBLE PRECISION A( LDA, * ), C( * ), R( * )



     #include <sunperf.h>

     void dlaqge(int m, int n, double *da, int  lda,  double  *r,
               double  *dc,  double rowcnd, double colcnd, double
               amax, char *equed) ;

PURPOSE
     DLAQGE equilibrates a general M by N matrix A using the  row
     and scaling factors in the vectors R and C.


ARGUMENTS
     M         (input) INTEGER
               The number of rows of the matrix A.  M >= 0.

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

     A         (input/output) DOUBLE PRECISION  array,  dimension
               (LDA,N)
               On entry, the M by  N  matrix  A.   On  exit,  the
               equilibrated  matrix.   See  EQUED for the form of
               the equilibrated matrix.

     LDA       (input) INTEGER
               The leading dimension of  the  array  A.   LDA  >=
               max(M,1).

     R         (input) DOUBLE PRECISION array, dimension (M)
               The row scale factors for A.

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

     ROWCND    (input) DOUBLE PRECISION
               Ratio of the smallest R(i) to the largest R(i).

     COLCND    (input) DOUBLE PRECISION
               Ratio of the smallest C(i) to the largest C(i).

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

     EQUED     (output) CHARACTER*1
               Specifies the form of equilibration that was done.
               = 'N':  No equilibration
               =  'R':   Row  equilibration,  i.e.,  A  has  been
               premultiplied  by diag(R).  = 'C':  Column equili-
               bration,  i.e.,  A  has  been  postmultiplied   by
               diag(C).   =  'B':  Both row and column equilibra-
               tion, i.e., A has been replaced by diag(R) *  A  *
               diag(C).

PARAMETERS
     THRESH is a threshold value used to decide if row or  column
     scaling  should  be  done  based  on the ratio of the row or
     column scaling factors.  If ROWCND < THRESH, row scaling  is
     done, and if COLCND < THRESH, column scaling is done.

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

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