@property<EOL><INDENT>def n200(self):<DEDENT>
if self._n200 is None:<EOL><INDENT>raise AttributeError('<STR_LIT>')<EOL><DEDENT>else:<EOL><INDENT>return self._n200<EOL><DEDENT>
Cluster richness values.

        If n200 is set directly, then mass m200 is calculated from n200
        using the mass-richness scaling relation specified by the
        parameters massrich_norm and massrich_slope. If m200 is set
        directly, then n200 is calculated from m200 using the same scaling
        relation. Changes to n200 will propagate to all mass-dependant
        variables.

        :property: Returns cluster richness values
        :property type: ndarray
        :setter: Sets cluster richness values
        :setter type: array_like