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It seems that I deleted accidentally the category. It was a mistake. Mariostorti 15:32, 21 May 2006 (UTC)
- Don't worry about it, mistakes like this happen all the time. -- Jitse Niesen (talk) 03:21, 22 May 2006 (UTC)
Preconditioning for linear systems section
I think that multiplying by preconditioners in a matrix free fashion is a detail that's not very important to understanding what a preconditioner is. It's a bit of a distraction and shouldn't be in the first paragraph. — Preceding unsigned comment added by 18.104.22.168 (talk) 23:07, 13 March 2013 (UTC)