How to compile this module?

*To*: mathgroup at smc.vnet.net*Subject*: [mg80882] How to compile this module?*From*: P_ter <peter_van_summeren at yahoo.co.uk>*Date*: Wed, 5 Sep 2007 02:41:12 -0400 (EDT)

Hello, I have some code in a Module and I would like to compile it so that Mathematica does not give complaints in execution: myM[lst_, W_] := Module [ {i, j = 1, len = Length@lst, res}, Reap[For[i = 1, i <= len, i++, While[lst[[j]] - lst[[i]] <= W && j < len, j++]; Sow[j - i]]; res] ] It works on this special constructed list (with a large number at the end): lst = {1, 2, 4, 5, 6, 9, 10, 12, 15, 1000}; The following is compiled by Mathematica: myC = Compile[{{lst, _Integer}, {W, _Integer}}, Module [ {i, j = 1, len = Length@lst, s, res}, Reap[For[i = 1, i <= len, i++, While[lst[[j]] - lst[[i]] <= W && j < len, j++]; Sow[j - i]]; res] ], {{res, _Integer, 4}} ] If Mathematica executes: myC[lst,2], it gives a message that the argument lst at position 1 should be a machine-size integer. Can anyone help? with friendly greetings, P_ter