Numpy no longer supports conversion of a one-element scalar array to an index.  Instead, we now manually convert the one-element array to a scalar.
@@ -438,7 +438,7 @@ class WESimManager:
for _i in xrange(n_istates_needed):
# Select a basis state according to its weight
ibstate = numpy.digitize([random.random()], self.next_iter_bstate_cprobs)
- basis_state = self.next_iter_bstates[ibstate]
+ basis_state = self.next_iter_bstates[ibstate[0]]
initial_state = self.data_manager.create_initial_states(1, n_iter=self.n_iter+1)[0]
initial_state.iter_created = self.n_iter
initial_state.basis_state_id = basis_state.state_id
