On Tue, 14 Sep 2010 01:58:07 pm aenea...@priest.com wrote:
> if len(rgenre)>0:
> if len(rgenre)>2:
> rg1=rgenre[0]
> rg2=rgenre[1]
> rg3=rgenre[2]
> elif len(rgenre)==2:
> rg1=rgenre[0]
> rg2=rgenre[1]
> rg3="NA"
> elif len(rgenre)==1:
> rg1=rgenre[0]
> rg2="NA"
> rg3="NA"
> else len(rgenre)<1: # I was hoping this would take care of the
> "there is no genre information" scenario but it doesn't
> rg1=rg2=rg3="NA"
The above will give a SyntaxError, because you can't have a condition
immediately after an else.
This is a neater way to write the above:
n = len(rgenre)
if n == 0:
rg1 = rg2 = rg3 = "NA"
elif n == 1:
rg1 = rgenre[0]
rg2 = rg3 = "NA"
elif n == 2:
rg1, rg2 = rgenre[0:2]
rg3 = "NA"
else:
rg1, rg2, rg3 = rgenre[:3]
which in turn can be shortened to the slightly cryptic one-liner:
rg1, rg2, rg3 = (rgenre + ["NA"]*3)[:3]
as already discussed earlier.
--
Steven D'Aprano
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