Problem 1022. Knot Count - Speed

Created by Richard Zapor

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6 Solutions
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Last Solution submitted on Nov 16, 2013

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Richard Zapor on 10 Nov 2012

The Knots Contest GradeIt function is not the number of Knots. FYI

Alfonso Nieto-Castanon on 13 Nov 2013

if possible could you fix the url in this problem testsuite? (and perhaps also in the Rubik's series as well? it seems tinyurls tend to have a short life...)

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Solution 352810

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2 Comments

Alfonso Nieto-Castanon on 16 Nov 2013

not really sure, but perhaps there are some numerical precision issues for some of the near-colinear cases in the testsuite? (if so perhaps it would be useful to resample the testsuite nodes to remove colinear or near-colinear cases?)

Richard Zapor on 16 Nov 2013

The expected knots table was based upon the Official slow scoring method. The docross function creates many warning messages "Warning: Matrix is singular to working precision. ". A single case, #3, takes >0.3 seconds versus expected 0.01 seconds.

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Problem 1022. Knot Count - Speed

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