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Message: [QUOTE="Dr J R Stockton, post: 4962094"] In comp.lang.javascript message <475e8b05$0$227$e4fe514c@news.xs4all.nl> , Tue, 11 Dec 2007 13:57:37, Erwin Moller <Since_humans_read_this_I_am_s [email]pammed_too_much@spamyourself.com[/email]> posted: That is a very bad way, in principle, of shuffling. <FAQENTRY> Don't do that. </FAQENTRY>. Method sort is, IIRC, defined to require a stable comparison; and with an unstable comparison the result is undefined. It might never finish ... . Follow Knuth. No need for using 1 & 2 to get that. A slight simplification of the standard shuffling algorithm gives a dealing algorithm. function Shuffle(Q) { var J, K, T for (J=Q.length-1 ; J>0 ; J--) { K = Random(J+1) ; T = Q[J] ; Q[J] = Q[K] ; Q[K] = T } return Q } function Deal(N) { var J, K, Q = new Array(N) for (J=0 ; J<N ; J++) { K = Random(J+1) ; Q[J] = Q[K] ; Q[K] = J } return Q } Those could no doubt be modified to look more similar. or 3a) Don't rebuild the arrays, but use MyIndexes to determine the order in which they are read out. Another approach - create a new array of objects (or of arrays) in which each object (or array) contains the corresponding elements of the original arrays. AOO[1] is {k:key1, v:value1} etc. Now randomize the array of objects, then either read out into separate arrays or use as they are. Yet another approach - use the function Shuffle above, but modified to take several array arguments (or an array of array arguments) and to have a single main loop which exchanges elements in the same manner in each array. The OP should have noted what the FAQ says about shuffle. It's a good idea to read the newsgroup c.l.j and its FAQ. See below. [/QUOTE]

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