ak.contents.ListOffsetArray

Defined in awkward.contents.listoffsetarray on line 56.

class ak.contents.ListOffsetArray(offsets, content, *, parameters=None)

ListOffsetArray describes unequal-length lists (often called a “jagged” or “ragged” array). Like ak.contents.RegularArray, the underlying data for all lists are in a contiguous content. It is subdivided into lists according to an offsets buffer, which specifies the starting and stopping index of each list.

The offsets must have at least length 1 (corresponding to an empty array), but it need not start with 0 or include all of the content. Just as ak.contents.RegularArray can have unreachable content if it is not an integer multiple of size, a ListOffsetArray can have unreachable content before the start of the first list and after the end of the last list.

Like ak.contents.RegularArray and ak.contents.ListArray, a ListOffsetArray can represent strings if its __array__ parameter is "string" (UTF-8 assumed) or "bytestring" (no encoding assumed) and it contains an ak.contents.NumpyArray of dtype=np.uint8 whose __array__ parameter is "char" (UTF-8 assumed) or "byte" (no encoding assumed).

ListOffsetArray corresponds to Apache Arrow List type.

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

class ListOffsetArray(Content):
    def __init__(self, offsets, content):
        assert isinstance(offsets, (Index32, IndexU32, Index64))
        assert isinstance(content, Content)
        assert len(offsets) != 0
        for i in range(len(offsets) - 1):
            start = offsets[i]
            stop = offsets[i + 1]
            if start != stop:
                assert start < stop  # i.e. start <= stop
                assert start >= 0
                assert stop <= len(content)
        self.offsets = offsets
        self.content = content

    def __len__(self):
        return len(self.offsets) - 1

    def __getitem__(self, where):
        if isinstance(where, int):
            if where < 0:
                where += len(self)
            assert 0 <= where < len(self)
            return self.content[self.offsets[where] : self.offsets[where + 1]]

        elif isinstance(where, slice) and where.step is None:
            offsets = self.offsets[where.start : where.stop + 1]
            if len(offsets) == 0:
                offsets = [0]
            return ListOffsetArray(offsets, self.content)

        elif isinstance(where, str):
            return ListOffsetArray(self.offsets, self.content[where])

        else:
            raise AssertionError(where)

_offsets

_content

property offsets: awkward.index.Index

form_cls: awkward._typing.Final

copy(offsets=UNSET, content=UNSET, *, parameters=UNSET)

classmethod simplified(offsets, content, *, parameters=None)

property starts: awkward.index.Index

property stops

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

_form_with_key_path(path: awkward.forms.form.FormKeyPathT) → awkward.forms.listoffsetform.ListOffsetForm

_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_ListOffsetArray64(start_at_zero: bool = False) → ListOffsetArray

to_RegularArray()

_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) → awkward.contents.content.Content

_compact_offsets64(start_at_zero: bool) → awkward.index.Index64

_broadcast_tooffsets64(offsets: awkward.index.Index) → ListOffsetArray

_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

_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

_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)

_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)

_rearrange_prepare_next(outlength, parents)

_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]

_drop_none() → awkward.contents.content.Content

_rebuild_without_nones(none_indexes, new_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

_awkward_strings_to_nonfinite(nonfinit_dict)

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