Update the params.

def _update_params(self, constants):
        """Update the params."""
        constants = np.max(np.min(constants, 1))
        self.params['r']['value'] = max([self.params['r']['value'],
                                         constants])
        epsilon = constants / self.params['r']['value']
        influence = self._calculate_influence(epsilon)
        # Account for learning rate
        return influence * epsilon