Extracting the u, v, w-coordinates from a CASA Measurement Set.

Should you want to extract the u, v (and w) coverage of your CASA data into e.g. a text file, rather than simply viewing it plotms(), then the following steps can be taken within CASA. Once in the text file the data is then easy to export into plotting packages etc.

Within CASA:

import numpy

numpy.set_printoptions(threshold='nan') #This prevents numpy truncating the print out of large arrays.

tb.open('your.ms', nomodify=F) #Opens your Measurement Set

uvw = tb.getcol('UVW') #Puts UVW data information into array uvw.

uvw_col = uvw.transpose() #transposes uvw array into uvw_col such that there are 3 columns representing u v and w values.

numpy.savetxt('namefile',uvw_col) # saves uvw_col to a text file named 'namefile'.

tb.close()#Closes your Measurement Set

The text file 'namefile' will then contain 3 columns representing u, v and w visbility values.