Thanks Patrick, that is what I was exactly looking for. Paul, thanks for your example. wasn't familiar with the stack class. I feel Patrick's method is a lot simpler for my purpose.
Regards. On Apr 8, 1:29 pm, Patrick Maupin <pmau...@gmail.com> wrote: > On Apr 8, 3:21 pm, "M. Hamed" <mhels...@hotmail.com> wrote: > > > > > I have trouble with some Python concept. The fact that you can not > > assign to a non-existent index in an array. For example: > > > a = [0,1] > > a[2] =========> Generates an error > > > I can use a.append(2) but that always appends to the end. Sometimes I > > want to use this array as a stack and hence my indexing logic would be > > something like: > > > If you are already at the end (based on your stack pointer): > > use append() then index (and inc your pointer) > > if not: > > index directly (and inc your stack pointer) > > > If feel that doing this everytime I want to add an element that I have > > to check whether it exists or not is too much. Is there any simpler > > way to do this? > > > I know I can do something like this: > > > a = numpy.zeros(MAX_STACK_SIZE) > > > but I don't want to predetermine the stack size. > > > Any help? > > > Thanks > > Well, if you never want to add intermediate data between your new > element and the stack, you can just do: > > stack[index:index + 1] = [newelement] > > Regards, > Pat -- http://mail.python.org/mailman/listinfo/python-list
