Comparing functionality in NEMO with like-wise programs in other packages can be helpful for onboarding. Here are a few examples:
Comparing NEMO programs with those in other packages| NEMO | python | CASA | MIRIAD |
|---|---|---|---|
| tabtrend | numpy.diff() | N/A | N/A |
| tabplot | plt.plot() | N/A | N/A |
| tabhist | plt.hist() | N/A | N/A |
| fitsccd | hdu=astropy.io.fits.open() | importfits() | fits op=xyin |
| ccdfits | hdu=astropy.io.fits.open() | exportfits() | fits op=xyout |
| ccdprint | print(hdu[0].data) | ??? | imlist |
| ccdmom | numpy.sum() | immoments() | moment |
| ccdmath | numpy | immath() | maths |
| ccdstat | hdu[0].data.std() | imstat() | imstat |
| ccdplot | numpy.contour | imview() | implot,cgdisp |
The CASA users guide has a more expanded table of this, just comparing CASA with MIRIAD and CLICK. There it is called a CASA-MIRIAD and CASA-CLIC dictionary.
An expanded example how to read a FITS (image) into the respective systems is as follows, plus some sample commands one can in the respective package:
# NEMO
$ fitsccd ngc0001.fits ngc0001.ccd
$ ccdhead ngc0001.ccd
$ ccdplot ngc0001.ccd yapp=/xs
# PYTHON
In [1]: hdu = astropy.io.fits.open('ngc0001.fits')
In [2]: print(hdu[0].header)
In [2]: plt.imshow(hdu[0].data)
# CASA
CASA <1>: importfits('ngc0001.fits', 'ngc0001.im')
CASA <2>: imhead('ngc0001.im')
CASA <2>: imview('ngc0001.im')
# MIRIAD
$ fits in=ngc0001.fits out=ngc0001.mir op=xyin
$ imhead in=ngc0001.mir
$ implot in=ngc0001.mir device=/xs