def __init__(self, ps, landscape):
self._ps = ps
self._landscape = landscape
self._nx, self._ny = landscape.shape
#Check if the simulation should end if an individual leaves the landscape bounds
self._break_on_leave = ps.max_distance and (
ps.max_distance < self._nx / 2. or ps.max_distance < self._ny / 2.)
#Calculate the number of individuals to seed each of the initial source locations.
self._ips = np.floor(self._ps.ips / len(self._ps.isl))
#Construct the population and dispersal sub-models
self._pmodel = Population_Model(ps)
self._dmodel = Dispersal_Model(ps, landscape)
