Re: Converting List of Tuples to List of Strings

Rich Shepard wrote:
>    I'm stuck in a rut and have not found a way out.
>
>    Records are retrieved from a sqlite table and stored in a list. In another
> module (and function) I retrieve these records and want to use their
> contents with other data in a different table.
>
>    When I access the data, e.g., 'print appData.polEco' I see this:
>
> [(u'Jobs',), (u'Infrastructure',), (u'Housing',), (u'Tax Base',), (u'Traffic
> Volume',), (u'Roads',), (u'Medical care',), (u'Sustainability',)]
>   
Hi Rich,
This should get you started again ...

 >>> x = [(u'Jobs',), (u'Infrastructure',), (u'Housing',), (u'Tax 
Base',), (u'Traffic Volume',), (u'Roads',), (u'Medical care',), 
(u'Sustainability',)]
 >>> x
[(u'Jobs',), (u'Infrastructure',), (u'Housing',), (u'Tax Base',), 
(u'Traffic Volume',), (u'Roads',), (u'Medical care',), (u'Sustainability',)]
 >>> y = [this[0] for this in x] # retain only the first element of each 
tuple in *x*
 >>> y
[u'Jobs', u'Infrastructure', u'Housing', u'Tax Base', u'Traffic Volume', 
u'Roads', u'Medical care', u'Sustainability']
 >>>

-- jv
>    I can extract each tuple, for i in range(len(appData.polEco)), and this
> gives me a list of individual tuples:
>
> (u'Jobs',)
> (u'Infrastructure',)
> (u'Housing',)
> (u'Tax Base',)
> (u'Traffic Volume',)
> (u'Roads',)
> (u'Medical care',)
> (u'Sustainability',)
>
>    Then, when I want to use these with other data:
>
> values = ('eco', appData.polEco[i], ecoVec[i])
> appData.cur.execute("insert or replace into importance (cat, comp, imp_wt)
> values (?,?,?)", values)
>
>    python responds:
>
> pysqlite2.dbapi2.InterfaceError: Error binding parameter 1 - probably
> unsupported type.
>
>    Printing values gives:
>
> ('eco', (u'Roads',), 0.073969887301348305)
>
>    so I assume it's the extra parentheses and unicode mark causing the
> problem. But, I've not been able to remove them when I've tried to slice
> them off.
>
>    How do I handle this?
>
> Rich
>
>