From mboxrd@z Thu Jan  1 00:00:00 1970
From: jt@sourceware.cygnus.com
To: gsl-cvs@sourceware.cygnus.com
Subject: gsl/linalg linalg_simple.c
Date: Sun, 17 Oct 1999 23:47:00 -0000
Message-id: <19991018064751.18638.qmail@sourceware.cygnus.com>
X-SW-Source: 1999/msg00340.html
List-Id: <gsl-cvs.sourceware.org>

CVSROOT:	/cvs/gsl
Module name:	gsl
Changes by:	jt@sourceware.cygnus.com	99/10/17 23:47:51

Modified files:
	linalg         : linalg_simple.c 

Log message:
	i was trying to use the SVD routine in linalg/linalg_simple.c,
	and it was producing singular values that were saturating at
	about 10^-6, even though the true values were much smaller than
	that.  i was able to "fix" the problem by replacing
	GSL_DBL_EPSILON with GSL_DBL_MIN, but i am suspicious of this
	solution.  perhaps the true test should be GSL_DBL_EPSILON times
	some scale factor? despite the fact that SVD always seems a
	little magical to me, and despite the likelihood that it will
	break some other case, i've gone ahead and cvs commit'd the
	change.  my own testing code, i must confess, is too convoluted
	to include here, but the test i did was a 10x10 Hilbert matrix:
	A[i][j] = 1/(i+j+2), i=0..9, j=0..9