title: Replace values in dataframe Python
body: <pre><code>Lon_X        Lat_Y
  5,234234     6,3234234
  5,234234     6,3234234
  5,234234     6,3234234
  5,234234     6,3234234
  5,234234     6,3234234
  </code></pre>
  
  <p>I've GPS coordinates in a pandas/dataframe like above. These however use the comma separator. What's the best way using pandas to convert these to float GPS coordinates?</p>
  
  <pre><code>for item in frame.Lon_X:
      float(item.replace(",", ".")) # makes the conversion but does not store it back
  </code></pre>
  
  <p>I've tried the iteritems function, but seems very slow and gives me a warning that I don't really understand:</p>
  
  <pre><code>for index, value in frame.Lon_X.iteritems():
      frame.Lon_X[index] = float(value.replace(",", "."))
  </code></pre>
  
  <blockquote>
    <p>See the caveats in the documentation:
    <a href="http://pandas.pydata.org/pandas-docs/stable/indexing.html#indexing-view-versus-copy" rel="nofollow noreferrer">http://pandas.pydata.org/pandas-docs/stable/indexing.html#indexing-view-versus-copy</a>
    from ipykernel import kernelapp as app</p>
  </blockquote>