Method align_indexes

xarray/structure/alignment.py:395–508

Compute all aligned indexes and their corresponding coordinate variables.

(self)

            return lambda _: None

    def align_indexes(self) -> None:
        """Compute all aligned indexes and their corresponding coordinate variables."""

        aligned_indexes: dict[MatchingIndexKey, Index] = {}
        aligned_index_vars: dict[MatchingIndexKey, dict[Hashable, Variable]] = {}
        reindex: dict[MatchingIndexKey, bool] = {}
        new_indexes: dict[Hashable, Index] = {}
        new_index_vars: dict[Hashable, Variable] = {}

        def update_dicts(
            key: MatchingIndexKey,
            idx: Index,
            idx_vars: dict[Hashable, Variable],
            need_reindex: bool,
        ):
            reindex[key] = need_reindex
            aligned_indexes[key] = idx
            aligned_index_vars[key] = idx_vars

            for name, var in idx_vars.items():
                if name in new_indexes:
                    other_idx = new_indexes[name]
                    other_var = new_index_vars[name]
                    raise AlignmentError(
                        f"cannot align objects on coordinate {name!r} because of conflicting indexes\n"
                        f"first index: {idx!r}\nsecond index: {other_idx!r}\n"
                        f"first variable: {var!r}\nsecond variable: {other_var!r}\n"
                    )
                new_indexes[name] = idx
                new_index_vars[name] = var

        for key, matching_indexes in self.all_indexes.items():
            matching_index_vars = self.all_index_vars[key]
            dims = {d for coord in matching_index_vars[0].values() for d in coord.dims}
            index_cls = key[1]

            if self.join == "override":
                joined_index = matching_indexes[0]
                joined_index_vars = matching_index_vars[0]
                need_reindex = False
            elif key in self.indexes:
                joined_index = self.indexes[key]
                joined_index_vars = self.index_vars[key]
                cmp_indexes = list(
                    zip(
                        [joined_index] + matching_indexes,
                        [joined_index_vars] + matching_index_vars,
                        strict=True,
                    )
                )
                need_reindex = self._need_reindex(dims, cmp_indexes)
            else:
                if len(matching_indexes) > 1:
                    need_reindex = self._need_reindex(
                        dims,
                        list(zip(matching_indexes, matching_index_vars, strict=True)),
                    )
                else: