CASA Contributed Script: getgain

Plotting VLA gain tables

Download script: File:Getgain.py

This utility reads the EVLA GainCurves file distributed with CASA and makes a plot for a specified antenna and band. It is meant to run inside of casa, but is located in its own file. Here is the usage:

getgain(myAntenna, myBand, myElev=60, tableLocation='')

There are 2 required arguments. The first argument is the antenna: either an integer number (1..28, 29=PieTown, 30=all, and 0=mean) or a string name in the form of 'ea03'. The second argument is the band letter: 4, P, L, S, C, X, U, K, A, Q. Note that 'S' band (as of May 2012) has no entries. An optional third argument is the elevation (in degrees) for which to report the gain. An optional fourth argument is the path to the GainCurves file, which is assumed to be $CASAPATH/data/nrao/VLA/GainCurves.

gain curve of ea03 at K-band

Here is an example:

# In CASA
CASA <4>: execfile('getgain.py')     or      from getgain import *
CASA <5>: getgain(3,'K',45.0)

elev=45.000000
band=K
antenna=3
current time = 4829398371.042835
Using table =  /usr/lib64/casapy/release/data/nrao/VLA/GainCurves
There are 250 rows with band K
There are 8 rows with antenna 3 and band K: 475 532 558 587 616 645 673 703 
Using row number 703
gain=1.026696 at ZA=45.0 or EL=45.0
Plot stored in gaincurve.K.3.png