This OTW code uses Ra,Dec coordinates from a cdfp file to generate a ds9-style regions file. The region markers are circle of a user-specified color and radius. The name for each marker is normally the line number, but read near the end of this doc about how to add extra infomation, like a Blue magnitude value, to the plotted name label.

 
 
%  cdfp2reg.sh file.cdfp 5.0 red X_pixel Y_pixel 
%  cdfp2reg.sh file.cdfp 5.0 red any any 

Usage: cdfp2reg.sh file 5.0 red X_pixel Y_pixel
Usage: cdfp2reg.sh file 5.0 red any any 
arg1 - name of input cdfp file
arg2 - output circle region radius in units of ARCSEC 
arg3 - output circle color
arg4 - name of X value (if desired, otherwise any)
arg5 - name of Y value (if desired, otherwise any)
Additional options: 
     -v = print verbose comments 
 --help = view a help document 

ADDED Jun2020:  You can set a minimum aperture radius with local file = cdfp2reg.MinApPix
% cat cdfp2reg.MinApPix 
6.0

The names attached to each output region is usually just the running line number in the input cdfp file. However, if a quantity name "label" is contined in the cdfp file, that that number (converted to an integer) is used as the name. You can rread about an example of using the label quantity for a name.

Notice that at the end of the example above I mention the cdfp2reg.MinApPix file. If this file is present, then a minimum aperture radius, whether we are printing in units of pixels or arcseconds, is specified. If this file is present, the code reads and imposes that value. This is useful when we want to generate files forcomputing aperture magnitudes using and input source catalog from image_catalogs. In such catalogs we may encounter lots of sources with only a few pixels and an equivalent radius that is just one or 2 pixels. We'd never want to use and aperture this small. Hence, codes line reg_from_imgcat use this capability to create regions files with reasonable apertures for even very small/faint detections. The figure below demonstrates this feature.

Here are some apertures gathered from a catalog created with the image_catalogs routine. % cdfp2reg.sh 20191018T024545.3_acm_sci.cdfp 5.0 red Xcent Ycent % mv 20191018T024545.3_acm_sci.cdfp.reg run1.reg % cat cdfp2reg.MinApPix 6.0 % cdfp2reg.sh 20191018T024545.3_acm_sci.cdfp 5.0 green Xcent Ycent % mv 20191018T024545.3_acm_sci.cdfp.reg run2.reg For the above figure I simply displayed the image then manually loaded the run1.reg and run2.reg files. In this cas the run1.reg marlers (red) have the all apertures plotted with an equivalent radius based on the number of thesholded pixels in the sours (Npix). In the run2.reg case (green), the equivalent radius is again used, but anything smaller than the value is cdfp2reg.MinApPix is replaced by that value.

Another useful routine for drawing bold, labeled circles at Ra,Dec positions is make_circles_bold.py:

% cat set.1
11:08:47.1552 +24:08:22.7148   9.0    0.0 0.0    cirle      green   "TextName" 

    RAsex        DECsec      Radius    X   Y   region_type  color   Text_String


% make_circles_bold.py set.1 > my_markers.reg
% cat my_markers.reg | xpaset ds9 regions -format ds9

There are often many columns in a cdfp file. The header line will show what is present in a given *.cdfp. It is sometimes desirable to add the values of these columns when labeling points in a region file. If you create a file named "extra.quantities" that conatins the name of your desired quantity (like "V" or "magR2", or "Blue") then the quantity will be included follwing the point name in the text label. This is used in creating the V and magR2 region sets in the usno_look script. Such region files are easy to build and handy to have around.

If I plot with "V" option I get scaled circle sizes. Here is how I did it.

By using a radius=-5.0 values I was able to turn off the portion of the aperture title builder that adds the magnitude value. Because the magnitude specified in the "extra.quantity" file was "magR2", we still get the circle sizes that are scaled to reflect the magnitude of each star. % cdfp2reg.sh dss_RA19c22c47p570DEC+53c20c40p33_297_usno_all.cdfp -5.0 cyan any any

By using a radius=+5.0 values I was able to get scaled circle sizes AND the magnitudes listed in each aperture title. Because the magnitude specified in the "extra.quantity" file was "magR2", we get the circle sizes that are scaled to reflect the magnitude of each star. % cdfp2reg.sh dss_RA19c22c47p570DEC+53c20c40p33_297_usno_all.cdfp +5.0 red any any