def _create_pedestrians(self):
        desired_velocities = []
        for a in setup.generate_pedestrians(self.parameters, 
                self.parameters['start_areas'], self.parameters['initial_count']):
            desired_velocities.append(a['initial_desired_velocity'])
            optimised.add_pedestrian(a)

        self.average_desired_velocity = np.average(desired_velocities)
    def _spawn(self):
        spawn_rate = self.parameters['continuous_rate']
        self.spawn_count += self.timestep * spawn_rate
        spawn = 0
        while self.spawn_count > 1.0:
            spawn += 1
            self.spawn_count -= 1.0

        if spawn > 0:
            for a in setup.generate_pedestrians(self.parameters,
                    self.parameters['continuous_start'], spawn):
                optimised.add_pedestrian(a)