Re: [bug-gnuastro] failure on wcscat,sh, radec.sh, wcspolygon.sh

[Mohammad Akhlaghi]

Hi Christopher,

Thanks again for this final check, I really appreciate it.

Infact my research is also on the high-redshift galaxies, so please 
don't hesitate to ask any issue that comes up or suggestions that you 
might have.

In particular for measuring colors, NoiseChisel makes the job very easy, 
since it doesn't output catalogs, its output is actually object and 
clump segmentation maps along with image noise statistics as described here:

https://www.gnu.org/software/gnuastro/manual/html_node/NoiseChisel-output.html

You then feed this output into another Gnuastro program called 
`MakeCatalog' to generate a catalog:

https://www.gnu.org/software/gnuastro/manual/html_node/MakeCatalog.html

The great thing with this modularity is that you can change any of the 
separate NoiseChisel outputs to other images. For example if you use the 
same segmentation maps, but different input image (and its statistics), 
you will get magnitudes of exactly the same objects/clumps in the other 
color. As another example, if you want aperture photometry, you can 
ignore NoiseChisel's segmentation maps and make elliptical apertures 
using MakeProfiles and use those as inputs into MakeCatalog.

I discussed the great advantages of this modularity for creative 
research in the ADASS, you can see the slides and the short proceedings 
article in the links below:

http://www.adass2016.inaf.it/images/presentations/01_Akhlaghi.pdf
https://arxiv.org/abs/1611.06387

I hope that the manual's coverage of the options to all these programs 
are enough to describe how you can do all of these.

The NoiseChisel program its self is also fully described in this ApJS 
(220, 1) article:

https://arxiv.org/abs/1505.01664

Thank you very much for your patient help in fixing this issue,
Cheers,
Mohammad