def get_unwise_tractor_image(basedir,
tile,
band,
bandname=None,
masked=True,
**kwargs):
'''
masked: read "-m" images, or "-u"?
bandname: PhotoCal band name to use: default: "w%i" % band
'''
if bandname is None:
bandname = 'w%i' % band
mu = 'm' if masked else 'u'
# Allow multiple colon-separated unwise-coadd directories.
basedirs = basedir.split(':')
foundFiles = False
for basedir in basedirs:
thisdir = get_unwise_tile_dir(basedir, tile)
base = os.path.join(thisdir, 'unwise-%s-w%i-' % (tile, band))
imfn = base + 'img-%s.fits' % mu
ivfn = base + 'invvar-%s.fits.gz' % mu
# ppfn = base + 'std-%s.fits.gz' % mu
nifn = base + 'n-%s.fits.gz' % mu
nufn = base + 'n-u.fits.gz'
if not os.path.exists(imfn):
print('Does not exist:', imfn)
continue
print('Reading', imfn)
wcs = Tan(imfn)
twcs = ConstantFitsWcs(wcs)
F = fitsio.FITS(imfn)
img = F[0]
hdr = img.read_header()
H, W = img.get_info()['dims']
H, W = int(H), int(W)
roi = interpret_roi(twcs, (H, W), **kwargs)
if roi is None:
# No overlap with ROI
return None
# interpret_roi returns None or a tuple; drop the second element in the tuple.
roi, nil = roi
(x0, x1, y0, y1) = roi
wcs = wcs.get_subimage(x0, y0, x1 - x0, y1 - y0)
twcs = ConstantFitsWcs(wcs)
roislice = (slice(y0, y1), slice(x0, x1))
img = img[roislice]
if not os.path.exists(ivfn) and os.path.exists(
ivfn.replace('.fits.gz', '.fits')):
ivfn = ivfn.replace('.fits.gz', '.fits')
if not os.path.exists(nifn) and os.path.exists(
nifn.replace('.fits.gz', '.fits')):
nifn = nifn.replace('.fits.gz', '.fits')
if not os.path.exists(nufn) and os.path.exists(
nufn.replace('.fits.gz', '.fits')):
nufn = nufn.replace('.fits.gz', '.fits')
if not (os.path.exists(ivfn) and os.path.exists(nifn)
and os.path.exists(nufn)):
print('Files do not exist:', ivfn, nifn, nufn)
continue
foundFiles = True
break
if not foundFiles:
raise IOError('unWISE files not found in ' + str(basedirs) +
' for tile ' + tile)
print('Reading', ivfn)
invvar = fitsio.FITS(ivfn)[0][roislice]
if band == 4:
# due to upsampling, effective invvar is smaller (the pixels
# are correlated)
invvar *= 0.25
# print 'Reading', ppfn
#pp = fitsio.FITS(ppfn)[0][roislice]
print('Reading', nifn)
nims = fitsio.FITS(nifn)[0][roislice]
if nufn == nifn:
nuims = nims
else:
print('Reading', nufn)
nuims = fitsio.FITS(nufn)[0][roislice]
# print 'Median # ims:', np.median(nims)
good = (nims > 0)
invvar[np.logical_not(good)] = 0.
sig1 = 1. / np.sqrt(np.median(invvar[good]))
# Load the average PSF model (generated by wise_psf.py)
psffn = os.path.join(os.path.dirname(__file__), 'wise-psf-avg.fits')
print('Reading', psffn)
P = fits_table(psffn, hdu=band)
psf = GaussianMixturePSF(P.amp, P.mean, P.var)
sky = 0.
tsky = ConstantSky(sky)
# if opt.errfrac > 0:
# nz = (iv > 0)
# iv2 = np.zeros_like(invvar)
# iv2[nz] = 1./(1./invvar[nz] + (img[nz] * opt.errfrac)**2)
# print 'Increasing error estimate by', opt.errfrac, 'of image flux'
# invvar = iv2
tim = Image(data=img,
invvar=invvar,
psf=psf,
wcs=twcs,
sky=tsky,
photocal=LinearPhotoCal(1., band=bandname),
name='unWISE %s W%i' % (tile, band))
tim.sig1 = sig1
tim.roi = roi
tim.nims = nims
tim.nuims = nuims
tim.hdr = hdr
if 'MJDMIN' in hdr and 'MJDMAX' in hdr:
from tractor.tractortime import TAITime
tim.mjdmin = hdr['MJDMIN']
tim.mjdmax = hdr['MJDMAX']
tim.time = TAITime(None, mjd=(tim.mjdmin + tim.mjdmax) / 2.)
return tim
