def rfd_poisson(ps,n):
"""Sample n configs by conditioning on chromosomal occupancy via LeCam's theorem"""
lam = sum(ps)
G = len(ps)
sample_q = lambda:nprandom.poisson(lam) # chromosomal occupancy approximately poisson.
sampler = make_sampler(ps)
return [direct_sampling_ps(ps,sample_q(),sampler) for i in xrange(n)]
def rfd_pois_binom(ps):
"""Sample a config by conditioning on chromosomal occupancy via
Poisson binomial distribution (LeCam's theorem approach proved
unsatisfactory), in blocks"""
q = inv_cdf_sample_fast(lambda k:dpois_binom(ps,k))
return direct_sampling_ps(ps,q)