table of contents
other versions
- wheezy 3.4.1+dfsg-1+deb70u1
- jessie 3.5.0-4
- jessie-backports 3.7.0-1~bpo8+1
- testing 3.7.0-2
- unstable 3.7.0-2
dlaqsp.f(3) | LAPACK | dlaqsp.f(3) |
NAME¶
dlaqsp.f -SYNOPSIS¶
Functions/Subroutines¶
subroutine dlaqsp (UPLO, N, AP, S, SCOND, AMAX, EQUED)
Function/Subroutine Documentation¶
subroutine dlaqsp (characterUPLO, integerN, double precision, dimension( * )AP, double precision, dimension( * )S, double precisionSCOND, double precisionAMAX, characterEQUED)¶
DLAQSP Purpose:DLAQSP equilibrates a symmetric matrix A using the scaling factors in the vector S.
UPLO
N
AP
S
SCOND
AMAX
EQUED
Internal Parameters:
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
N is INTEGER The order of the matrix A. N >= 0.
AP is 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 is DOUBLE PRECISION array, dimension (N) The scale factors for A.
SCOND is DOUBLE PRECISION Ratio of the smallest S(i) to the largest S(i).
AMAX is DOUBLE PRECISION Absolute value of largest matrix entry.
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 = 'Y': Equilibration was done, i.e., A has been replaced by diag(S) * A * diag(S).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.
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
November 2011
Author¶
Generated automatically by Doxygen for LAPACK from the source code.Sun May 26 2013 | Version 3.4.1 |