Adding additional columns to the tool page

Not sure if this has been covered or not but I could not find it. 
I am not very familiar with gmoccapy so help is appreciated. 
I would like to add and remove some columns in the tool page of gmoccapy.
I can do the programming, I just mainly need to know which file would be relevant.
For example: How would I add the "U" column? 

Edit: How would I DISPLAY the "U" column?
The columns that are not displayed are still there and being read, they just are not displayed on the tool page.


Thank you
 

Bump

Anyone?

Gmoccapy will add the columns corresponding to your INI settings. If you want to change that behavior, you will need to touch the code in gmoccapy. Py file. Search for init_tooltable or similar and add the columns you need by python code.

Norbert 

I needed to add the "v" column.
I modified the "/usr/bin/gmoccapy" file (I'm running version 2.8.1)
Edit the file /usr/bin/gmoccapy
Lines 1817 thru 1820 are existing lines.
Add line 1821

Line 1817:  # first we hide all the axis columns the unhide the ones we want
Line 1818:  self.widgets.tooledit1.set_visible("abcxyzuvwijq", False)
Line 1819:  for axis in self.axis_list:
Line 1820:       self.widgets.tooledit1.set_visible("{0}".format(axis), True)
Line 1821:       self.widgets.tooledit1.set_visible("v", True)