I've replied below. On Jun 6, 2008, at 3:11 PM, Justin To wrote: > modArr = Array.new > freq = Array.new([ [0] ]) > values = Array.new([ [] ]) > > > #--------------Open the output file and process each line----- > File.open('output.txt', 'r').each { |x| > > #-------------Create unique keys according to |x|--------------- > #--Calculate the modulus ([add each digit]%10) and use it as hash > key-- > key = 0; modF = x.each_byte { |y| key += y.chr.to_i } > #--For slight optimization, change the resulting key into a symbol > mod = (key%100).to_s.intern > > > #--If the key D.N.E. then add it into modArr > > if(!modArr.include?(mod)) > > #--Add the value > values[modArr.size][0] = x.chomp > > > #--Add the frequency > freq[modArr.size][0] += 1 > > > #--Add the mod > modArr[modArr.size] = mod > > > end > > } > > > Hi, I'm still trying to work on the same problem that I posted a few > days ago... when i run this program, this error reads: > > BLANK.rb:22: undefined method `[]=' for nil:NilClass (NoMethodError) > from BLANK.rb:7:in `each' > from BLANK.rb:7 > > > Why is this? And how do I fix it?? You're using a rather unconventional way of appending to an array, i.e. ary[ary.size] = value. This works in the general case. Where it doesn't work is in your code where you say, effectively, ary[ary.size] [0] = value. The problem is that ary[ary.size] is returning nil. -Kevin Ballard -- Kevin Ballard http://kevin.sb.org kevin / sb.org http://www.tildesoft.com