Viewer Additions

CASA Modification Request 16C108, November 2007

1. Introduction

Continued improvement of the casa viewer is suggested.

2. Background

3. Requirements

The viewer will evolve over time. The following improvements (and minor bugs) are listed:

1. For most plots, the x-axis of baselines in uvdist would be useful. The uvdist most appropriate is the baseline separation on the ground and not projected u-v distance.

2. Plot the vector average over all channels, with the option of flagging all channels.

3. A clipping facility which will enable outlier points to be removed. See the clip option in the aips task TVFLG.

4. Can the viewer be used in a script to obtain hard copies of displays, contour plots, etc. This would require the viewer to obtain parameter information non-interactively. This might be accomplished using the restore/save facility in the script. For example, the aips++ viewer could be controlled from a glish script; the present viewer cannot.

5. Current postscript output is unacceptable. If people cannot make publication quality figures, they will not want to use this software. This should not be low priority since it gives a bad impression of the package, and is one of the worst postscript packages.

6. Annotation additions to the postscript (or whatever) output is needed as soon as possible.

7. Placement and rendering of color wedge is awkward and rarely what you want. In the case of fairly square images you can eventually mess with the canvas manager enough to make it look reasonable, but for rectangular images it is often impossible. Note that the aips++ viewer had the same problem and it seems to have been replicated here.

8. When you enter a beam manually in casa (because this information is missing in the header) the statistics function in the viewer fails to recognize that the beam is present (i.e. it will not calculate the integrated flux density). Despite this, the beam is drawn on the image so the viewer itself knows the beam is there. [][JIRA Ticket CAS-385]]

9. It would be extremely useful if the viewer would simultaneously display BOTH the requested coordinate reference frame AND the pixel number. Currently if you wanted to extract a profile at a particular position, it is time consuming and imprecise to find the right coordinate position and then figure out which pixel it corresponds to [][JIRA Ticket CAS-219]]

10. Related to point 4 above. It should be possible to save all of the details of the "canvas" well enough that you really can come back and make changes to an image that you've already made. Figure creation must be repeatable.

11. It must be possible to make multi-panel plots similar to those in the AIPS task KNTR. That is, the panels maximize the canvas space with labels only along the outside panels. You should also be able to display the z-axis coordinate in each panel (i.e. label each panel with its velocity for example).

4. Design

5. Deployment Checklist

6. Test Plan

6.1 Internal Testing

6.2 Sponsor Testing

6.3 Integration/Regression Tests

6.4 Testing for Scientific Validity


APPROVED: I acknowledge that my request is fully contained in this MR, and if the CASA development group delivers exactly what I specified, I will be happy.

ACCEPTED: I acknowledge that I have validated the completed code according to the acceptance tests, and I am happy with the results.

Written - - - - -
Checked - - - - -
Approved by Scientific Sponsor - - - - -
Accepted/Delivered by Sponsor - - - - -

  • Use %X% if MR is not complete (will display ALERT!)
  • Use %Y% if MR iscomplete (will display DONE)

Discussion Area

-- NicoleRadziwill - 30 Oct 2007

-- EdFomalont - 06 Nov 2007
Topic revision: r4 - 2007-11-23, EdFomalont
This site is powered by FoswikiCopyright © by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding NRAO Public Wiki? Send feedback