LAPACK
3.5.0
LAPACK: Linear Algebra PACKage

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Functions/Subroutines  
subroutine  dlaqge (M, N, A, LDA, R, C, ROWCND, COLCND, AMAX, EQUED) 
DLAQGE scales a general rectangular matrix, using row and column scaling factors computed by sgeequ. More...  
subroutine dlaqge  (  integer  M, 
integer  N,  
double precision, dimension( lda, * )  A,  
integer  LDA,  
double precision, dimension( * )  R,  
double precision, dimension( * )  C,  
double precision  ROWCND,  
double precision  COLCND,  
double precision  AMAX,  
character  EQUED  
) 
DLAQGE scales a general rectangular matrix, using row and column scaling factors computed by sgeequ.
Download DLAQGE + dependencies [TGZ] [ZIP] [TXT]DLAQGE equilibrates a general M by N matrix A using the row and column scaling factors in the vectors R and C.
[in]  M  M is INTEGER The number of rows of the matrix A. M >= 0. 
[in]  N  N is INTEGER The number of columns of the matrix A. N >= 0. 
[in,out]  A  A is 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. 
[in]  LDA  LDA is INTEGER The leading dimension of the array A. LDA >= max(M,1). 
[in]  R  R is DOUBLE PRECISION array, dimension (M) The row scale factors for A. 
[in]  C  C is DOUBLE PRECISION array, dimension (N) The column scale factors for A. 
[in]  ROWCND  ROWCND is DOUBLE PRECISION Ratio of the smallest R(i) to the largest R(i). 
[in]  COLCND  COLCND is DOUBLE PRECISION Ratio of the smallest C(i) to the largest C(i). 
[in]  AMAX  AMAX is DOUBLE PRECISION Absolute value of largest matrix entry. 
[out]  EQUED  EQUED is 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 equilibration, i.e., A has been postmultiplied by diag(C). = 'B': Both row and column equilibration, i.e., A has been replaced by diag(R) * A * diag(C). 
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.
Definition at line 142 of file dlaqge.f.