def write_legacysurvey_randoms(input_fn, truth_fn, randoms_fn, bricknames=[], seed=None):
"""Build Obiwan randoms from legacysurvey randoms and truth table."""
randoms = SimCatalog(input_fn)
logger.info('Selecting randoms in %s' % bricknames)
mask = np.in1d(randoms.brickname,bricknames)
randoms = randoms[mask]
randoms.rename('targetid','id')
logger.info('Selected random catalog of size = %d.' % randoms.size)
randoms.keep_columns('id','ra','dec','maskbits','photsys','brickname')
for photsys in ['N','S']:
truth = get_truth(truth_fn,south=photsys=='S')
mask = randoms.photsys == photsys
if mask.any():
randoms.fill(sample_from_truth(randoms[mask],truth,seed=seed),index_self=mask,index_other=None)
randoms.writeto(randoms_fn)
def get_truth(truth_fn, south=True):
"""Build truth table."""
truth = SimCatalog(truth_fn)
mask = (truth.g >= 22.) & (truth.g <= 24.)
for b in ['g','r','z']:
mask &= (~np.isnan(truth.get(b))) & (~np.isinf(truth.get(b)))
logger.info('Target selection: %d/%d objects' % (mask.sum(),mask.size))
truth = truth[mask]
truth.rename('objid','id_truth')
truth.rename('rhalf','shape_r')
#truth.shape_r = 1e-5*truth.ones()
truth.rename('hsc_mizuki_photoz_best','redshift')
truth.sersic = truth.ones(dtype=int)
truth.sersic[truth.type=='DEV'] = 4
return truth
def get_truth(truth_fn, south=True):
"""Build truth table."""
truth = SimCatalog(truth_fn)
mask = isELG_colors(south=south,
gmarg=0.5,
grmarg=0.5,
rzmarg=0.5,
**{
'%sflux' % b: utils.mag2nano(truth.get(b))
for b in ['g', 'r', 'z']
})
for b in ['g', 'r', 'z']:
mask &= (~np.isnan(truth.get(b))) & (~np.isinf(truth.get(b)))
logger.info('Target selection: %d/%d objects' % (mask.sum(), mask.size))
truth = truth[mask]
truth.rename('objid', 'id_truth')
truth.rename('rhalf', 'shape_r')
#truth.shape_r = 1e-5*truth.ones()
truth.rename('hsc_mizuki_photoz_best', 'redshift')
truth.sersic = truth.ones(dtype=int)
truth.sersic[truth.type == 'DEV'] = 4
return truth