HOW-TO Visualize observational pointings with ObsViewer (OLD)

ObsViewer can query the database for RawScienceFrames or ReducedScienceFrames for a given rectangular region of the sky, wavelength range and range in exposure time. It can output the results in a figure and ascii files.

NOTE1: EXPERIMENTAL VERSION. Bug reports and other feedback welcome: Gijs Verdoes Kleijn (verdoes@astro.rug.nl)

NOTE2: ONLY WFI OBSERVATIONAL POINTINGS ARE QUERIED.

Example 1 of use at the awe-prompt

awe> from astro.experimental.ObsViewer import ObsViewer
awe> o = ObsViewer()
awe> o.query_database(rastart=174, raend=178, decstart=-5, decend=-5,
                      central_lambdastart=4000.0, central_lambdaend=5000.0,
                      expomin=0.0, expomax=200.0,raw='yes')
awe> o.preview(newplot=1, plotcolor='b', plotsize=20)
awe> o.plot(plotfov=1, fillfov=1, newplot=1, plotcolor='b',
            plotsize=20, sec_per_dot=1.0)

The command lines have the following effects:

1. IMPORTS MODULE INTO AWE ENVIRONMENT.

2. MAKES A CLASS INSTANTIATION.

3. QUERIES THE DATABASE.

   Input parameters:
   • rastart/end: (degrees) start and end right ascension of rectangular region in the sky.
   • decstart/end: (degrees) start and end declination of rectangular region in the sky.
   • central_lambdastart/end: (Angstrom) start and end of wavelength region in which the central wavelength of the exposure filter has to be.
   • expomin/max: (sec) minimum/maximum exposure time for exposure.
   • raw: query for raw images (raw=’yes’) or reduced images (raw=’no’).
   Result:

   a query which can be used by o.preview and o.plot.
4. PLOTS AND SAVES A FIGURE CONTAINING ONLY THE POINTING CENTERS OF THE QUERY RESULTS.

   Input parameters:
   • newplot: make a new plot (newplot=1) or overplot on an existing one (newplot=0)?
   • plotcolor: color of plotting symbol: color=’r’ means red, and b:blue, g:green, c:cyan, m:magenta, y:yellow, k:black, w:white.
   • plotsize: size of the plotting symbol to plot.
   Output:

   a figure (png format) named ObsViewer_ra_\(<\)rastart\(>\)_\(<\)raend\(>\)_dec_\(<\)decstart\(>\)_\(<\)decend\(>\)-_lambda_:math:<lambdastart\(>\)_\(<\)lambdaend\(>\)_expo_\(<\)expomin\(>\)_\(<\)expomax\(>\)_preview.png (see Figure [f:preview]).

   NOTE: the tool buttons on the bottom of the graphical display window can be used to zoom in on parts of the figure.

5. PLOTS AND SAVES A FIGURE VISUALIZING THE QUERY RESULT AND WRITES AN OUTPUT FILE WITH THE RESULTS.

   Input parameters:
   • plotfov: plot the field of view (FOV) around the pointing centers (0=no, 1=yes)?
   • fillfov: fill the FOV with random poisson points (to emphasize overlapping exposures) (0=no, 1=yes)?
   • sec_per_dot: the number seconds exposure time per dot plot by fillfov. For example, sec_per_dot=10.0 plots a dot for each ten seconds of exposure time.
   • plotcolor: color of plotting symbol: color=ŕ’ means red, and b:blue, g:green, c:cyan, m:magenta, y:yellow, k:black, w:white.
   • plotsize: size of the plotting symbol to plot.
   Outputs:

   A graphical display window with the result.

   A figure (png format) named ObsViewer_ra_\(<\)rastart\(>\)_\(<\)raend\(>\)_dec_\(<\)decstart\(>\)_\(<\)decend\(>\)-_lambda_:math:<lambdastart\(>\)_\(<\)lambdaend\(>\)_expo_\(<\)expomin\(>\)_\(<\)expomax\(>\).png (see Figure [f:plot]). A text file (ascii format) named ObsViewer_ra_\(<\)rastart\(>\)_\(<\)raend\(>\)_dec_\(<\)decstart\(>\)_\(<\)decend\(>\)-_lambda_:math:<lambdastart\(>\)_\(<\)lambdaend\(>\)_expo_\(<\)expomin\(>\)_\(<\)expomax\(>\).txt.

   NOTE: the tool buttons on the bottom of the graphical display window can be used to zoom in on parts of the figure.

Example 2

awe> from astro.experimental.ObsViewer import ObsViewer
awe> o = ObsViewer()
awe> o.query_database(rastart=170, raend=180, decstart=-20, decend=-20, central_lambdastart=4000.0, central_lambdaend=5000.0, expomin=0.0, expomax=200.0, raw='yes')
awe> o.plot(plotfov=1, fillfov=1, newplot=1, plotcolor='b', plotsize=20, sec_per_dot=1.0)
awe> o.query_database(rastart=170, raend=180, decstart=-20, decend=-20, central_lambdastart=5000.0, central_lambdaend=6000.0, expomin=0.0, expomax=200.0, raw='yes')

awe> o.plot(plotfov=1, fillfov=1, newplot=0, plotcolor='g', plotsize=20, sec_per_dot=1.0)

Command lines have the following effects:

-.4: similar to steps in example 1.

Now the query is made for frames with a central_lambda different from step 3

The result from the query in step 5 is overplotted in green on the existing plot from step 4 (see Figure 3).

Figure 1: Example output figure from awe> o.preview(). The circles indicate the centers of the pointings

Figure 2: Example output figure from awe> o.plot(plotfov=1,fillfov=1). The rectangles represent the FOV of the exposure to scale. The random dots (by setting fillfov=1) reflect the exposure time as explained in example 1.

Figure 3: Example output figure from two queries as in example 2. The rectangles represent the FOV of the exposure to scale. The random dots (by setting fillfov=1) reflect the exposure time as explained in example 1.