STARS module

stars is the pyvista module that implements routines for dealing with stellar images

mark : interactively add stars to internal list

photom : do aperture photometry of stars on internal list

save : save internal list to file

get : load internal list from file

stars functions:

class pyvista.stars.Center(x, y, tot, meanprof, varprof)

meanprof

Alias for field number 3

tot

Alias for field number 2

varprof

Alias for field number 4

x

Alias for field number 0

y

Alias for field number 1

pyvista.stars.find(data, fwhm=4, thresh=4000, sharp=[0.0, 1.0], round=[-2.0, 2.0], brightest=None)

Star finding using DAOStarfinder

Parameters

• data (array-like) – 2D data array

• fwhm (optional, float) – FWHM (pixels) for matching, default=4

• thresh (optional, float) – Threshold above background, default=4000

• sharp (optional, [float,float]) – Low and high bounds for sharpness, default=[0.,1.]

• round (optional, [float,float]) – Low and high bounds for roundness, default=[-2.,2]

pyvista.stars.automark(data, stars, header=None, rad=3, func='centroid', plot=None, dx=0, dy=0, verbose=False, background=True)

Recentroid existing star list on input data array

pyvista.stars.mark(tv, stars=None, rad=3, auto=False, color='m', new=False, exit=False, id=False, func='centroid')

Interactive mark stars on TV, or recenter current list

Args :

tv : TV instance from which user will mark stars stars = : existing star table auto= (bool) : if True, recentroid from existing position radius= (int): radius to use for centroiding and for size of circles (default=3) color= (char) : color for circles (default=’m’)

pyvista.stars.sdss_label(t, im, label='psfmag_g', maxmag=19, rad=0.25, xoff=0, yoff=-10)

inital stab for getting SDSS coords and labelling image

pyvista.stars.photom(data, stars, uncertainty=None, mask=None, rad=[3], skyrad=None, display=None, gain=1, rn=0, mag=True, utils=True, cum=False)

Aperture photometry of input image with current star list

pyvista.stars.get(file)

Read FITS table into internal photometry list

pyvista.stars.save(file, stars)

Save internal photometry list to FITS table

pyvista.stars.process_all(files, red, tab, bias=None, dark=None, flat=None, threads=8, display=None, solve=True, seeing=15, rad=[3, 5, 7], skyrad=[10, 15], cards=['EXPTIME', 'FILTER', 'AIRMASS'])

multi-threaded processing of files

pyvista.stars.process(file, red, tab, bias=None, dark=None, flat=None, display=None, solve=True, seeing=15, rad=[3, 5, 7], skyrad=[10, 15], cards=['EXPTIME', 'FILTER', 'AIRMASS'])

Process and do photometry on input file

pyvista.stars.diffphot(tab, aper='aper35.0', yr=0.1, title=None, hard=None)

Make differential photometry plots including airmass detrending