On Tue, Feb 8, 2011 at 2:47 PM, Christian Witts <cwi...@compuscan.co.za>
>>> `while i< len(c)` instead of `while 1`
>>>
>>
>> You remind me of me...like it was yesterday. Explanations with no
>> thought. Unimpressive isn't it?
>>
>
> While the index is smaller than the length of the string do your processing.
> It reads like that. But thank you for your commentary.
>
The goal of this list is not to criticize, David, but to help. Why not
provide some explanations yourself?
EIther way, even with this correction a ValueError is still raised at
least *once* if the string doesn't end with a 0, so it won't actually
help a bit. A quick fix is to set some variable if you find a 0, then
check on that variable after the loop (See Peter's example).
Now, find is nice if you care about finding one instance, but if you
need to find *all* instances you'll have to check the entire string
anyway, and find becomes a rather cumbersome tool. Interestingly,
enumerate was suggested all the way at the beginning of the thread,
and I think it's the best answer:
zeroes = ["lane fail {0}".format(i) for i, val in enumerate(c) if val == '0']
print '\n'.join(zeroes) if zeroes else "All Lanes pass"
Ok, That looks a little advanced, but strip away all that syntactic
sugar and you arrive at basically this:
zeroes = []
for index, value in enumerate(c):
if value == '0':
zeroes.append(index)
if zeroes:
for x in zeroes:
print "lane fail", x
else:
print "all lanes pass"
Since we have to scan the whole string anyway, this is equally
efficient as using find (theoretically!!! if you care about
performance, *measure*).
Hugo
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