Re: Strange problem with "for" and "while"

*To*: mathgroup at smc.vnet.net*Subject*: [mg68374] Re: Strange problem with "for" and "while"*From*: Peter Pein <petsie at dordos.net>*Date*: Thu, 3 Aug 2006 06:06:34 -0400 (EDT)*References*: <eapru8$s5i$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

LordBeotian schrieb: > When I try to compute this: > > For[k = 1, k < 10, k++, > i := 0; > While [k > 1, i++; k--]; > Print[i, k]] > > Mathematica outputs a neverending sequence of "1,1" (and it is impossible to > abort the computation!) > > When instead I try to manually do the "for" and compute > > k := ...; > i = 0; > While [k > 1, i++; k--]; > Print[i, k] > > giving to k all the values 1,2,...,9 the computation are all correct (the > outputs are "01", "11", "21", ..., "81". > > I cannot understand what is the problem. > Hi, your While-loop destroys the k used in For[]. try either For[k = 1, k < 10, k++, i = 0; j = k; While[j > 1, i++; j--]; Print[i, j]] or simply Print[#, 1] & /@ Range[0, 8]; hth, Peter