LAPACK 3.12.0
LAPACK: Linear Algebra PACKage

subroutine slaqsy  (  character  uplo, 
integer  n,  
real, dimension( lda, * )  a,  
integer  lda,  
real, dimension( * )  s,  
real  scond,  
real  amax,  
character  equed  
) 
SLAQSY scales a symmetric/Hermitian matrix, using scaling factors computed by spoequ.
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SLAQSY equilibrates a symmetric matrix A using the scaling factors in the vector S.
[in]  UPLO  UPLO is CHARACTER*1 Specifies whether the upper or lower triangular part of the symmetric matrix A is stored. = 'U': Upper triangular = 'L': Lower triangular 
[in]  N  N is INTEGER The order of the matrix A. N >= 0. 
[in,out]  A  A is REAL array, dimension (LDA,N) On entry, the symmetric matrix A. If UPLO = 'U', the leading n by n upper triangular part of A contains the upper triangular part of the matrix A, and the strictly lower triangular part of A is not referenced. If UPLO = 'L', the leading n by n lower triangular part of A contains the lower triangular part of the matrix A, and the strictly upper triangular part of A is not referenced. On exit, if EQUED = 'Y', the equilibrated matrix: diag(S) * A * diag(S). 
[in]  LDA  LDA is INTEGER The leading dimension of the array A. LDA >= max(N,1). 
[in]  S  S is REAL array, dimension (N) The scale factors for A. 
[in]  SCOND  SCOND is REAL Ratio of the smallest S(i) to the largest S(i). 
[in]  AMAX  AMAX is REAL Absolute value of largest matrix entry. 
[out]  EQUED  EQUED is 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 = 'Y': Equilibration was done, i.e., A has been replaced by diag(S) * A * diag(S). 
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.
Definition at line 132 of file slaqsy.f.