ak.contents.IndexedArray#

Defined in awkward.contents.indexedarray on line 57.

class ak.contents.IndexedArray(index, content, *, parameters=None)#

IndexedArray is a general-purpose tool for lazily changing the order of and/or duplicating some content with a np.take over the integer buffer index.

It has many uses:

representing a lazily applied slice.
simulating pointers into another collection.
emulating the dictionary encoding of Apache Arrow and Parquet.

If the __array__ parameter is "categorical", the contents must be unique. Some operations are optimized (for instance, == only compares index integers) and the array can be converted to and from Arrow/Parquet’s dictionary encoding.

To illustrate how the constructor arguments are interpreted, the following is a simplified implementation of __init__, __len__, and __getitem__:

class IndexedArray(Content):
    def __init__(self, index, content):
        assert isinstance(index, (Index32, IndexU32, Index64))
        assert isinstance(content, Content)
        for x in index:
            assert 0 <= x < len(content)  # index[i] must not be negative
        self.index = index
        self.content = content

    def __len__(self):
        return len(self.index)

    def __getitem__(self, where):
        if isinstance(where, int):
            if where < 0:
                where += len(self)
            assert 0 <= where < len(self)
            return self.content[self.index[where]]

        elif isinstance(where, slice) and where.step is None:
            return IndexedArray(
                self.index[where.start : where.stop], self.content
            )

        elif isinstance(where, str):
            return IndexedArray(self.index, self.content[where])

        else:
            raise AssertionError(where)

_index#

_content#

property index#

form_cls: awkward._typing.Final#

copy(index=UNSET, content=UNSET, *, parameters=UNSET)#

classmethod simplified(index, content, *, parameters=None)#

_form_with_key(getkey: awkward._typing.Callable[[awkward.contents.content.Content], str | None]) → awkward.forms.indexedform.IndexedForm#

_form_with_key_path(path: awkward.forms.form.FormKeyPathT) → awkward.forms.indexedform.IndexedForm#

_to_buffers(form: awkward.forms.form.Form, getkey: awkward._typing.Callable[[awkward.contents.content.Content, awkward.forms.form.Form, str], str], container: collections.abc.MutableMapping[str, awkward._nplikes.array_like.ArrayLike], backend: awkward._backends.backend.Backend, byteorder: str)#

_to_typetracer(forget_length: bool) → awkward._typing.Self#

_touch_data(recursive: bool)#

_touch_shape(recursive: bool)#

property length: awkward._nplikes.shape.ShapeItem#

_repr(indent, pre, post)#

to_IndexedOptionArray64() → awkward.contents.indexedoptionarray.IndexedOptionArray#

mask_as_bool(valid_when: bool = True) → awkward._nplikes.array_like.ArrayLike#

_getitem_nothing()#

_is_getitem_at_placeholder() → bool#

_is_getitem_at_virtual() → bool#

_getitem_at(where: awkward._nplikes.numpy_like.IndexType)#

_getitem_range(start: awkward._nplikes.numpy_like.IndexType, stop: awkward._nplikes.numpy_like.IndexType) → awkward.contents.content.Content#

_getitem_field(where: str | awkward._typing.SupportsIndex, only_fields: tuple[str, Ellipsis] = ()) → awkward.contents.content.Content#

_getitem_fields(where: list[str | awkward._typing.SupportsIndex], only_fields: tuple[str, Ellipsis] = ()) → awkward.contents.content.Content#

_carry(carry: awkward.index.Index, allow_lazy: bool) → IndexedArray#

_getitem_next_jagged_generic(slicestarts, slicestops, slicecontent, tail)#

_getitem_next_jagged(slicestarts: awkward.index.Index, slicestops: awkward.index.Index, slicecontent: awkward.contents.content.Content, tail) → awkward.contents.content.Content#

_getitem_next(head: awkward._slicing.SliceItem | tuple, tail: tuple[awkward._slicing.SliceItem, Ellipsis], advanced: awkward.index.Index | None) → awkward.contents.content.Content#

project(mask=None)#

_offsets_and_flattened(axis: int, depth: int) → tuple[awkward.index.Index, awkward.contents.content.Content]#

_mergeable_next(other: awkward.contents.content.Content, mergebool: bool, mergecastable: awkward._typing.Literal[same_kind, equiv, family]) → bool#

_merging_strategy(others)#

_reverse_merge(other)#

_mergemany(others: collections.abc.Sequence[awkward.contents.content.Content]) → awkward.contents.content.Content#

_fill_none(value: awkward.contents.content.Content) → awkward.contents.content.Content#

_local_index(axis, depth)#

_unique_index(index, sorted=True)#

_numbers_to_type(name, including_unknown)#

_is_unique(negaxis, starts, parents, offsets, outlength)#

_unique(negaxis, starts, parents, offsets, outlength)#

_argsort_next(negaxis, starts, shifts, parents, offsets, outlength, ascending, stable)#

_sort_next(negaxis, starts, parents, offsets, outlength, ascending, stable)#

_combinations(n, replacement, recordlookup, parameters, axis, depth)#

_reduce_next(reducer, negaxis, starts, shifts, parents, offsets, outlength, mask, keepdims, behavior)#

_validity_error(path)#

_nbytes_part()#

_pad_none(target, axis, depth, clip)#

_to_arrow(pyarrow: awkward._typing.Any, mask_node: awkward.contents.content.Content | None, validbytes: awkward.contents.content.Content | None, length: int, options: awkward.contents.content.ToArrowOptions)#

_to_cudf(cudf: awkward._typing.Any, mask: awkward.contents.content.Content | None, length: int)#

_to_backend_array(allow_missing, backend)#

_remove_structure(backend: awkward._backends.backend.Backend, options: awkward.contents.content.RemoveStructureOptions) → list[awkward.contents.content.Content]#

_recursively_apply(action: awkward.contents.content.ImplementsApplyAction, depth: int, depth_context: collections.abc.Mapping[str, awkward._typing.Any] | None, lateral_context: collections.abc.Mapping[str, awkward._typing.Any] | None, options: awkward.contents.content.ApplyActionOptions) → awkward.contents.content.Content | None#

_to_packed(recursive: bool = True) → awkward._typing.Self#

_to_list(behavior, json_conversions)#

_to_backend(backend: awkward._backends.backend.Backend) → awkward._typing.Self#

_materialize(type_) → awkward._typing.Self#

property _is_all_materialized: bool#

property _is_any_materialized: bool#

_push_inside_record_or_project() → awkward._typing.Self | awkward.contents.RecordArray#

_is_equal_to(other: awkward._typing.Self, index_dtype: bool, numpyarray: bool, all_parameters: bool) → bool#

_trim() → awkward._typing.Self#