"Bryan Fodness" <[EMAIL PROTECTED]> wrote
I have a list in a text file that is in the python format.,
Positions = [2.5,2.8]
When you say "in the Python format" do you mean it
is real Python codfe or just that it happens to look
like Python?
If the latter what format is it really? If its a config file then
the config parser will extract the string based on the key
(positions) for you. But you will still need to convert the
string "[2.5,2.8]" to a list or tuple.
You could use eval to evaluate the string but that would
be dangerous since the striong could be a malicious
piece of code. But you can make it a lot safer by wrapping
it in a function with known effect, thus:
s = "[2.5,2.8]" # your string from the file
e = "tuple(" + e + ")"
x,y = eval(e) # x -> 2.5, y -> 2.8
Now if some crazy code gets read by error the eval
will throw an error. Its not foolproof but it works for all but
the most devious attacks.
If you don't like that then it's down to parsing the string
and I'd suggest a regular expression is best to pull out
the numbers unless the string is definitely fixed format/length.
HTH,
--
Alan Gauld
Author of the Learn to Program web site
http://www.freenetpages.co.uk/hp/alan.gauld
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