Method _divisions

dask/dataframe/dask_expr/_expr.py:1877–1892

(self)

        return {}

    def _divisions(self):
        if not self.is_monotonic:
            # Implement this consistently with dask.dataframe, e.g. add option to
            # control monotonic map func
            return (None,) * len(self.frame.divisions)
        elif is_index_like(self.frame._meta):
            return tuple(
                pd.Series(self.frame.divisions).map(self.arg, na_action=self.na_action)
            )
        elif isinstance(self.arg, Expr):
            if self.arg.divisions == self.frame.divisions:
                return self.frame.divisions
            else:
                # We only get here when we have only one partition
                return (None,) * (self.frame.npartitions + 1)
        return super()._divisions()


class VarColumns(Elemwise):