def select_rows(self, rows):
        ''' Truncate internal arrays to keep only the specified rows.

        Args:
            rows (array): An integer or boolean array identifying the indices
                of rows to keep.
        '''
        self.values = self.values.iloc[rows]
        self.index = self.index.iloc[rows, :]
        for prop in self._property_columns:
            vals = getattr(self, prop)[rows]
            setattr(self, prop, vals)
Truncate internal arrays to keep only the specified rows.

        Args:
            rows (array): An integer or boolean array identifying the indices
                of rows to keep.