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Timeline for Optimizing the condition number

Current License: CC BY-SA 3.0

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Sep 3, 2015 at 13:36 history edited Denis Serre CC BY-SA 3.0
edited body
Aug 16, 2012 at 16:35 vote accept Igor Rivin
Aug 16, 2012 at 16:29 answer added Suvrit timeline score: 12
Aug 16, 2012 at 13:52 answer added Federico Poloni timeline score: 5
Aug 16, 2012 at 13:13 comment added Igor Rivin OK, this is now fixed.
Aug 16, 2012 at 13:13 history edited Igor Rivin CC BY-SA 3.0
flipped the condition number
Aug 16, 2012 at 13:12 comment added Igor Rivin @Federico and @Suvrit: of course you are right, I want SMALL condition numbers. Will fix.
Aug 16, 2012 at 9:06 comment added Federico Poloni sorry, I meant "inverse of the condition number", not "reverse".
Aug 16, 2012 at 7:39 comment added Federico Poloni @Igor: given Suvrit's remark, maybe you were thinking about the reverse condition number when writing? Typically people want to get small condition numbers, not large ones.
Aug 16, 2012 at 6:45 comment added Suvrit @Igor: The condition number of any matrix is always $\ge 1$, using a consistent norm, so am I misreading your question (because you say "...condition number is always 0...$)?
Aug 16, 2012 at 1:13 comment added Gerhard Paseman I don't know of anything theoretically better. Something that should work in practice is to do Gram Schmidt orthogonalization: when you choose the largest m/2 vectors and orthogonalize the rest, it makes sense to choose the longer of the remaining processed vectors to reach your goal. That should prune a lot of the search space. (I am assuming condition number is related to determinant.) Gerhard "Ask Me About System Design" Paseman, 2012.08.15
Aug 16, 2012 at 0:13 history asked Igor Rivin CC BY-SA 3.0