Seems someone beat us to entering this feature request: http://quality.runrev.com/show_bug.cgi?id=10919
On 24.05.2013, at 12:04, Dave Cragg wrote: > Nice one, Alex. I spent an hour convincing myself that the sA array could > contain duplicate elements after the loop, until the penny dropped. Remind me > never to play cards if you're shuffling. :-) > > Dave > > On 24 May 2013, at 00:41, Alex Tweedly <a...@tweedly.net> wrote: > >> >> Yes, that's a good shuffle for small data, but a bit slow for larger data >> sets. I dug out an old function I wrote a few years ago (and converted it to >> LC); this would be faster for large data sets (time taken grows linearly >> rather than by the square of the number of lines). >> >> local sA, sIndex -- filled with random shuffle index, returned one-by-one >> from fn calls >> >> function shuffleLines pSource >> put empty into tNew >> put the number of lines of pSource into tNum >> -- fill an array with 'self' numbers >> repeat with i = 1 to tNum >> put i into tA[i] >> end repeat >> >> repeat with n = tNum down to 1 >> put random(n) into tRand >> put tA[tRand] into sA[n] >> put tA[n] into tA[tRand] >> end repeat >> put 0 into sIndex >> sort lines of pSource by _shuffle() >> return pSource >> end shuffleLines >> >> function _shuffle >> add 1 to sIndex >> return sA[sIndex] >> end _shuffle >> >> -- Alex. >> > > > _______________________________________________ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your subscription > preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode -- Use an alternative Dictionary viewer: http://bjoernke.com/bvgdocu/ Chat with other RunRev developers: http://bjoernke.com/chatrev/ _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
