Nathan Pinno wrote:
>> store = open(filename,'r')
> for line in store:
> conv = line.strip()
> rate = float(store.next().strip())
> exch[conv] = rate
>
> When I ran the program, I got this:
>
> Traceback (most recent call last):
> File "D:\Python24\exchange.py", line 45, in -toplevel-
> load_rates(rates)
> File "D:\Python24\exchange.py", line 19, in load_rates
> rate = float(store.next().strip())
> StopIteration
>
> How do I fix this?
StopIteration is an iterator's way of saying it has reached the end. When you
iterate
using a for loop, the exception is caught internally and used to terminate the
loop. When
you call next() explicitly, you should be prepared to catch the exception
yourself.
In this case though, the exception means you have a conv without a rate, so it
is a
symptom of bad data or an error reading the data.
Have you looked at the file to make sure it is correct? If it is, you might try
a slightly
different loop. I'm not sure if it really works to mix a for loop iteration
with calls to
next() on the iterator. Try something like this:
store = open(filename,'r')
try:
while True:
conv = store.next().strip()
rate = float(store.next().strip())
exch[conv] = rate
except StopIteration:
pass
Or use the pickle module to save and load your exch dictionary, it is perfect
for this and
as simple as
import pickle
# save
store = open(filename, 'wb')
pickle.dump(exch, store)
store.close()
# load
store = open(filename, 'b')
exch = pickle.load(store)
store.close()
Kent
_______________________________________________
Tutor maillist - Tutor@python.org
http://mail.python.org/mailman/listinfo/tutor
