On Wednesday, September 21, 2016 at 12:30:49 AM UTC-7, Meinolf wrote:
> OMG, Is this normal?????
> i got chills telling me it had something to do with the *For Loop*, 
> played around with the LBs and UBs and the following worked:
>        * for i in range(-1, (len(getcourseids)-1)):*
>            * c = db.item.id <http://db.item.id>==getcourseids[i].item_id*
> *            s.append(db(c).select(db.item.course_title)[i])*
> Now i'm puzzled as to why give a lower bound of -1 for the range, will 
> this keep on working or my code could later crash???? I put it under a 
> *Try..Except 
> * block though..please help if there's a safer alternative, this is new 
> to me and sort of contradicts what i know of starting from 0.
The normal Python way of writing a loop on a list is:
     for id in getcourseid:
       c = db.item.id == id.item_id
Giving an explicit range would be appropriate if you were processing only a 
portion of the list, but there you could use Python slices to do that:
     for id in getcourseid[3:7]:

As for your effort to use villas' suggestion, you should have replace his "
values" with your "item_id".

You might want to scan Chapter 3 for some examples of Python coding and 
web2py queries.
and just below that, the wiki example, especially def show: and the 
pagecomments query.


- http://web2py.com
- http://web2py.com/book (Documentation)
- http://github.com/web2py/web2py (Source code)
- https://code.google.com/p/web2py/issues/list (Report Issues)
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