def read_from_tractor_cat(fn, same_keys=['ra', 'dec', 'type']):
'''returns data dict for DECaLS()
same_keys -- keys that have identical names b/w tractor cat and data dict expected by DeCALS()'''
from fits import tractor_cat
a = tractor_cat(fn)
data = {}
for k in same_keys:
data[k] = a[k]
data['type'] = np.char.strip(data['type'])
for band, ind in zip(['g', 'r', 'z'], [1, 2, 4]):
data[band + 'flux'] = a['decam_flux'][:, ind]
data[band + 'flux_ivar'] = a['decam_flux_ivar'][:, ind]
data[band + '_ext'] = a['decam_mw_transmission'][:, ind]
data[band + '_psf_fwhm'] = a['decam_psfsize'][:, ind]
for band, ind in zip(['w1'], [0]):
data[band + 'flux'] = a['wise_flux'][:, ind]
data[band + 'flux_ivar'] = a['wise_flux_ivar'][:, ind]
data[band + '_ext'] = a['wise_mw_transmission'][:, ind]
return data
class Grid(object):
def __init__(self,ramin,ramax,decmin,decmax,pixscale):
self.npix_ra= int(deg_to_arcsec(ramax-ramin)/pixscale + 1)
self.npix_dec= int(deg_to_arcsec(decmax-decmin)/pixscale + 1)
self.ra_centers= np.linspace(ramin,ramax,num=self.npix_ra)
self.dec_centers= np.linspace(decmin,decmax,num=self.npix_dec)
def nearest_cell_index(self,ra,dec):
'''return x,y index for img of nearest ra,dec pixel center to ra,dec'''
return np.argsort(np.abs(self.ra_centers-ra))[0], np.argsort(np.abs(self.dec_centers-dec))[0]
parser = ArgumentParser(description="test")
parser.add_argument("-cat",action="store",help='tractor catalogue')
parser.add_argument("-pixscale",type=float,action="store",help='tractor catalogue')
args = parser.parse_args()
cat=tractor_cat(args.cat)
grid= Grid(cat['ra'].min(),cat['ra'].max(),cat['dec'].min(),cat['dec'].max(),args.pixscale)
# size of image
W,H = grid.npix_ra,grid.npix_dec
# PSF size
psfsigma = 1.
# per-pixel noise
noisesigma = 1.e-2
# create tractor.Image object for rendering synthetic galaxy
# images
tim = Image(data=np.zeros((H,W)), invvar=np.ones((H,W)) / (noisesigma**2),
psf=NCircularGaussianPSF([psfsigma], [1.]))
def nearest_cell_index(self, ra, dec):
'''return x,y index for img of nearest ra,dec pixel center to ra,dec'''
return np.argsort(np.abs(self.ra_centers - ra))[0], np.argsort(
np.abs(self.dec_centers - dec))[0]
parser = ArgumentParser(description="test")
parser.add_argument("-cat", action="store", help='tractor catalogue')
parser.add_argument("-pixscale",
type=float,
action="store",
help='tractor catalogue')
args = parser.parse_args()
cat = tractor_cat(args.cat)
grid = Grid(cat['ra'].min(), cat['ra'].max(), cat['dec'].min(),
cat['dec'].max(), args.pixscale)
# size of image
W, H = grid.npix_ra, grid.npix_dec
# PSF size
psfsigma = 1.
# per-pixel noise
noisesigma = 1.e-2
# create tractor.Image object for rendering synthetic galaxy
# images
tim = Image(data=np.zeros((H, W)),