title: Extract columns by file name from Pandas dataframe
body: <p>I'm new to python and pandas.</p>
  <p>I made a Pandas DataFrame for my data like the picture below.
  I want to extract x_c and y_c columns grouped by the file name.
  For example, I want to make the new dataframe, let's say df1, which has the values of x_c and y_c with the &quot;file name&quot; of &quot;recon_image_0000.tif&quot;
  Then I want to make another dataframe, df2 in the same manner but the file name of &quot;recon_image_0001.tif&quot;.
  Like this way, I want to extract all the data and save separate till the last file name, &quot;recon_image_0036.tif&quot;.</p>
  <p>Can some one give me some tips to extract and make new pandas dataframe?
  <a href="https://i.stack.imgur.com/kT0gu.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/kT0gu.png" alt="enter image description here" /></a></p>