float from numbers in text file

[Stephen Hansen]

On 6/21/10 4:26 PM, davidgp wrote:
> ah, i see :P
> float("45.34") or whatever does work fine, but the problem is that i'm
> reading it from a text file. so somehow it is not a real string or
> whatever..
> here's a part of the code:
> f = open ('/home/david/out.txt', 'r')
> 
> for line in f:
> if tel ==6:
> 			buf = line.replace('\n', '')
> 			lat = float(buf)
> 		if tel ==7:
> 			buf = line.replace('\n', '')
> 			lng = float(buf)
> 
> basically it goes wrong in the last part where i try to convert the
> line to a float..
> i'm 100% sure that it's getting a number, not a text string
>

First: you don't have to strip \n's. Try float("45.43\n")

Second: this code, as is, can't run to show us the problem because
there's this "tel" business and I don't know what it is. But I'll tweak
it a bit and:

  f = open ('/Users/ixokai/out.txt', 'r')

  tel = 6
  for line in f:
     if tel == 6:
        buf = line.replace('\n', '')
        lat = float(buf)
        print lat
     if tel == 7:
        buf = line.replace('\n', '')
        lng = float(buf)

And it works fine with a dummy data file I have. So... the problem is
somewhere else. Its either in your data file, or some other logic going
on (maybe something related to this 'tel' thing, I don't know).

Are you sure there's no lines in out.txt which have, say, some text (on
the left end)? Or maybe some blank lines?

Maybe you should send the whole file and the data.txt if you don't see
where the problem is.

-- 

   Stephen Hansen
   ... Also: Ixokai
   ... Mail: me+list/python (AT) ixokai (DOT) io
   ... Blog: http://meh.ixokai.io/

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