Thread: Octave QP issue
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Old 08-24-2012, 12:17 PM
zifmia zifmia is offline
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Join Date: Jul 2012
Posts: 4
Default Re: Octave QP issue

Thanks for posting this. Went from only occasionally converging to converging always (N=100) or usually (N=10). Got all these answers correct on submission.

For N=10, I was finding that Octave failed to converge even on the modified problem about 10% of the time. For purposes of this assignment I just ignored these cases, but clearly there is more tweaking to be done. (Although other posts on Octave didn't seem to mention this, so perhaps there is something wrong with my problem formulation).

Followup: A quick experiment I should have done sooner shows that all of the cases that failed to converge were degenerate cases where all 10 points had the same classification. Apparently with my random line target and random point data this happens about 10% of the time with 10 points, and almost all of these fail to solve within the default 200 iterations. (Of course when they do solve, they have zero support vectors.)

Last edited by zifmia; 08-24-2012 at 12:36 PM. Reason: new data
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