[Tutor] Converting from unicode to nonstring

[Joel Goldstick]

On Fri, Oct 15, 2010 at 6:26 AM, David Hutto <smokefloat at gmail.com> wrote:

> Ok, Let me restate and hopefully further clarify.
>
> 1. I have a field for a wxpython app using matplotlib to display
>
> 2. I have a sqlite3 db which I'm retrieving information from
>
> 3. The sqlitle data is returned as unicode: u'field'
>
> 4. The portion of the matplotlib code is filled in, in a for x in y:
>
> 5. in plot(self.plot), self.plot is the variable I'm using from the
> unicoded db
> field comes in from sqlite as u'[1,2,3,4]', which places a string in quotes
> in
> that variables place:
>
> plot(u'[1,2,3,4]')
>
> 6. the plot(eval(self.plot)), changes the variable from the u'[1,2,3,4]'
> to just [1,2,3,4]
>
> 7 As stated somewhere above, the float error has nothing to do with
> the probel, only the fact that it was used as if I had placed ''
> around the necessary data from the db field.
>
> 8. If anyone has a way better than eval to convert the u'field' when
> replacing a variable so that
>
> self.plot = [1,2,3,4]
>
> instead of
>
> self.plot = u'[1,2,3,4]'
>
>
> Let me know, meanwhile I'll be reviewing the replies more thoroughly,
> now that I've had a nap.
>
>
> Thanks,
> David
>

This will do it

> So you want convert string u'1,2,3,4' to a list of ints [1,2,3,4]?
> Then the below will work.
>
> [int(n) for n in u'1,2,3,4'.replace(',', '')]
>
> Greets
> Sander
>

or this:

>>> s = '1, 200 , -3,4'  # or whatever
>>> [int(x) for x in s.split(',')]
[1, 200, -3, 4]


or this:

To take a string of comma separated integers and convert to a list of ints:

>>> x = u'1,2,3,4'
>>> y = x.split(',')
>>> z = [int(f) for f in y]
>>> z
[1.0, 2.0, 3.0, 4.0]
>>>


-- 
Joel Goldstick

You can forget about the u' in front.  Its a directive to the interpreter
that the following string is in unicode.
In your case u'1,2,3,4' is the same as '1,2,3,4'.

All of the above examples do this:

1. split the string up into 4 different strings in a tuple by removing the
commas ::   ('1', '2', '3', '4')
2. convert the individual string vales to integers and put them in a list ::
[1, 2, 3, 4]




--
Steven D'Aprano

Joel Goldstick
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