[GLLUG] The Python talk reminds me of a question...

[Jeremy Bowers]

Ashton Shortridge wrote:
> Here comes the question. I want to return ALL of the titles. Intuitively (but 
> wrongly), I tried:
> db[:][4]
> which returns an error that basically says there is no 4th element in the list 
> - meaning the list called db, which only contains two things. Other stabs 
> also met with failure.
> 
> So, the question is, how can I refer to the nth elements of ALL records?

The easiest way will be a list comprehension:

[x[4] for x in db]

Having a real example based on your code and needs might help you 
understand them better, as they are somewhat unusual.

That is equivalent to:

x = []
for _ in db:
     x.append(_[4])

where I use "_" because that variable never actually exists.

> If 
> the answer is: "hey silly, use a different data structure!" , then just tell 
> me about that structure.

Even if you use a different data structure, this is still often the 
right answer, the expression in front just changes. A class might read as

[x.title for x in db]

(If you have further followup questions, please feel free to email me, 
but we should probably take it off-list.)