Building lists

Seymore4Head Seymore4Head at Hotmail.invalid
Tue Oct 21 14:54:18 CEST 2014


On Tue, 21 Oct 2014 00:11:38 -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, it is not necessary, 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
>
>That creates a 50-element list with each element set to None.  (BTW, the indexes are from 0-49, 
>not 0-50.)  I have found this occasionally useful, but I'll emphasize, it's 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, 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 and use this for your exploration.  But realize 
>that to more experienced Pythonistas this would be a very un-pythonic approach.  Even better 
>would be to try multiple approaches -- lists, dictionaries, lists with dictionaries, 
>dictionaries with lists or tuples...  And any other combinations you can come up with.  This 
>will give you even more experience, and allow you to evaluate the different approaches.
>
>And no, I will not give you a ready-made "canned" answer.  For one thing, your description is 
>too vague to effectively do that.  Good luck.
>
>      -=- Larry -=-

The concept I was asking about was a master list with my example of
1,2,3 as a index for the second and third items.  It was suggested to
make my task easier.  It turns out that it didn't. 
Thanks for all the suggestions, though.



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