continue
if len(t.retrons) == 1:
transforms.append(t)
# Get a random sample of chemical compounds.
sample = Sample(chemicals, size=args.size, rng_seed=args.seed)
# Initialize data structures for stats gathering.
keys = ['accepted', 'valid', 'total']
new_stats = dict(zip(keys, len(keys) * [0]))
old_stats = dict(zip(keys, len(keys) * [0]))
# For each chemical in the sample perform a single retrosynthetic step.
reactions = {}
disconnected_count = 0
for chem_rec in sample.get():
try:
smi = chem_rec['smiles'].encode('ascii')
except (AttributeError, KeyError):
sys.stderr.write('Chemical {0} has no SMILES'.format(chem_rec['_id']))
continue
# Ignore disconnected chemicals, e.g. such as c1cc([O-].[Na+])ccc1,
# as we treat '.' (dot) as a compound separator.
if '.' in smi:
disconnected_count += 1
continue
try:
chem = Chemical(smi)
except ValueError:
