@property<EOL><INDENT>def density(self):<DEDENT>
tot_nonsparse = sum(ser.sp_index.npoints<EOL>for _, ser in self.items())<EOL>tot = len(self.index) * len(self.columns)<EOL>return tot_nonsparse / float(tot)<EOL>
Ratio of non-sparse points to total (dense) data points
represented in the frame