more newbie help needed

[Steve Holden]

john boy wrote:
> using the following program:
>  
> fruit = "banana"
> index = 0
> while index < len (fruit):
>      letter = fruit[index-1]
>      print letter
>      index= index -1
>  
> this program is supposed to spell "banana" backwards and in a vertical patern...it does this....but after spelling "banana" it gives an error message:
> refering to line 4: letter = fruit[index-1]
> states that it is an IndexError and the string index is out of range
> Anybody know how to fix this?
> 
Change the termination condition on your loop. If you print out the 
values of index as the loop goes round you'll see you are printing 
characters whose index values are -1, -2, ..., -6

Unfortunately -7 is less than -6, so your loop keeps on going, with the 
results you observe.

Note, however, that there are more pythonic ways to perform this task. 
You might try:

for index in range(len(fruit)):
   letter = fruit[-index-1]
   print letter

as one example. I'm sure other readers will have their own ways to do 
this, many of them more elegant.

regards
  Steve
-- 
Steve Holden       +44 150 684 7255  +1 800 494 3119
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