On Feb 25, 1:01 pm, [EMAIL PROTECTED] wrote:
> While working with lists of tuples is probably very common, none of my
> five Python books or a Google search tell me how to refer to specific items
> in each tuple. I find references to sorting a list of tuples, but not
> extracting tuples based on their content.
>
> In my case, I have a list of 9 tuples. Each tuple has 30 items. The first
> two items are 3-character strings, the remaining 28 itmes are floats.
>
> I want to create a new list from each tuple. But, I want the selection of
> tuples, and their assignment to the new list, to be based on the values of
> the first two items in each tuple.
>
> If I try, for example, writing:
>
> for item in mainlist:
item is one of your 30-element tuples, ...
> if mainlist[item][0] == 'eco' and mainlist[item][1] == 'con':
so do this:
if item[0] == 'eco' and item[1] == 'con':
> ec.Append(mainlist[item][2:])
and
ec.append(item[2:]) # note append, not Append
>
> python doesn't like a non-numeric index.
If nothing. Python doesn't like a non-numeric index, quite
irrespective of what you do :-)
> I would really appreciate a pointer
Sorry, only nasty languages have pointers :-)
> so I can learn how to manipulate lists
> of tuples by referencing specific items in each tuple (string or float).
HTH,
John
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