Building lists

Seymore4Head Seymore4Head at Hotmail.invalid
Tue Oct 21 14:55:31 CEST 2014


On Tue, 21 Oct 2014 00:40:06 -0700, Larry Hudson <orgnut at yahoo.com>
wrote:

>On 10/20/2014 12:49 PM, Seymore4Head wrote:
>> On Mon, 20 Oct 2014 20:40:18 +0100, MRAB <python at mrabarnett.plus.com>
>> wrote:
>>
>      <snip>
>
>> Do you have to know the number of items the list will have before
>> making it?
>>
>
>No.  Lists are NOT the same as arrays in other languages.  But it IS possible to create an 
>initial list of a specific size:
>
>myList = [None] * 50
>
>This creates a 50-element list with each element set to None.  (BTW, that makes the indexes 
>0-49, not 0-50.)  I have occasionally found this useful, but I emphasize it is only RARELY 
>useful.  The .append() method is far more versatile.
>
>As to your original problem:  my question to you is what is your purpose?
>
>1)  To solve this particular problem, using Python.
>   or
>2)  To explore the usage of lists by applying them to this problem.
>
>If your purpose is the first, then I agree with the advice you have already been given here -- 
>dictionaries are a much better fit to this problem.
>
>If your purpose is the second, then go ahead, have at it.  But realize that to more experienced 
>Pythonistas this approach the very un-pythonic for this problem.  It would be even better to try 
>multiple approaches -- lists, dictionaries, lists with dictionaries, dictionaries with lists or 
>tuples...  or whatever combination you can come up with.  This will give you even more 
>experience and allow you to evaluate these various techniques.
>
>And no, I won't give you a ready-made "canned" answer.  For one thing your original description 
>is much too vague.  But good luck!
>
>      -=- Larry -=-

Also, I had no need to impose a limit on the list, but I asked that
question, just in case.

Thanks



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