Plotting Phase and Amplitudes of a Measurement Set in CASA:

You have to work on CASA version 3803, therefore log into gns:

  • > ssh gns

Start CASA:

  • >casapy

This should start CASA version 3803, which seems more reliable than 4769.

Define the MS in which you wan't to work on:

  • zvis='' e.g zvis=''

  • vis=zvis

List the observations (will appear on the logger window)

  • listobs(zvis)

(Will list observation details, from there youcan retrieve the FieldID number for the sources and calibrators)

Indentify your pointing calibrator, phase calibrator and sources. And select either of these for the next set of plotting commands.





You can modify the individual parameters manually, by typing:

  • inp plotxy
  • Then for instance type: field='2', or xaxis='frequency' (not sure if working though)

Plot Amplitude versus time

plotxy(vis=zvis,xaxis="time",yaxis="amp",datacolumn="data",selectdata=True,antenna="0&1",spw="0",field=objectid,uvrange="",timerange="",correlation="",scan="",feed="",array="",average="chan",subplot=111,plotsymbol="+",plotcolor="blue",markersize=5.0,linewidth=1.0,connect="none",plotrange=[-1, -1, -1, -1],multicolor="corr",selectplot=False,overplot=False,newplot=False,clearpanel=True,skipnrows=1,averagenrows=1,title="",xlabels="",ylabels="",iteration="")

Plot Amplitude versus channel

  • plotxy(vis=zvis,xaxis="channel",yaxis="amp",datacolumn="data",selectdata=True,antenna="0&1",spw="0",field=objectid,uvrange="",timerange="",correlation="",scan="",feed="",array="",average="time",subplot=111,plotsymbol="+",plotcolor="blue",markersize=5.0,linewidth=1.0,connect="none",averagenrows=100,title="",xlabels="",ylabels="",iteration="",fontsize=10.0,windowsize=1.0,showflags=False)

Plot Phase versus time

After you have selected your object ID, you can run;

plotxy(vis=zvis,xaxis="time",yaxis="phase",datacolumn="data",selectdata=True,antenna="0&1",spw="0",field=objectid,uvrange="",timerange="",correlation="",scan="",feed="",array="",average="chan",subplot=111,plotsymbol="+",plotcolor="blue",markersize=5.0,linewidth=1.0,connect="none",plotrange=[-1, -1, -1,-1],multicolor="corr",selectplot=False,overplot=False,newplot=False,clearpanel=True,skipnrows=1,averagenrows=1,title="",xlabels="",ylabels="",iteration="")

LLC Correction

Using the script to plot amplitude and phases after LLC correction (requires you to download the LLC monitor files from archive).

unix> MonitorDataGUI &

> click Device=LLC

> click Property=Counter

> ctl-click Property=VF

> click Add Query

> click on "DA41/LLC:Counter" (should highlight entire row)

> enter date range e.g. 2008-04-15 17:00:00 to 2008-04-16 10:00:00

* > click "Query Raw"*

> save to "/groups/sci/interferometry/20080415/llc.aec.ctr.txt"

> click "DA41/LLC:VF" (highlights the row)

> click "Query Raw"

> save to "/groups/sci/interferometry/20080415/llc.aec.vf.txt"

> click "DV01/LLC:Counter" (highlights the row)

> click "Query Raw"

> save to "/groups/sci/interferometry/20080415/"

> click "DV01/LLC:VF" (highlights the row)

> click "Query Raw"

> save to "/groups/sci/interferometry/20080415/"

In interferometry/20080415/:

> unix> casapy --path "$PYTHONPATH"

> casa <1> execfile("../../casa/")

> casa <2> ampphase("",llcmode="archive")

Full Reduction in CASA:

Please refer to the following script, which has been used to reduce an Orion Spectrum. Written by R. Indebetouw.:


-- AntonioHales - 04 May 2008
Topic revision: r6 - 2008-05-23, AntonioHales
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