ak.contents.ListArray#
Defined in awkward.contents.listarray on line 52.
- class ak.contents.ListArray(self, starts, stops, content, *, parameters=None)#
ListArray generalizes ak.contents.ListOffsetArray by not
requiring its content to be in increasing order and by allowing it to
have unreachable elements between lists. Instead of a single offsets buffer,
ListArray has
starts: The starting index of each list.stops: The stopping index of each list.
ak.contents.ListOffsetArray offsets may be related to starts and
stops by
starts = offsets[:-1]
stops = offsets[1:]
ListArrays are a common by-product of structure manipulation: as a result of
some operation, we might want to view slices or permutations of the content
without copying it to make a contiguous version of it. For that reason,
ListArrays are more useful in a data-manipulation library like Awkward Array
than in a data-representation library like Apache Arrow.
Like ak.contents.ListOffsetArray and ak.contents.RegularArray, a ListArray 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).
There is no equivalent of ListArray in Apache Arrow.
To illustrate how the constructor arguments are interpreted, the following is a
simplified implementation of __init__, __len__, and __getitem__:
class ListArray(Content):
def __init__(self, starts, stops, content):
assert isinstance(starts, (Index32, IndexU32, Index64))
assert isinstance(stops, type(starts))
assert isinstance(content, Content)
assert len(stops) >= len(starts) # usually equal
for i in range(len(starts)):
start = starts[i]
stop = stops[i]
if start != stop:
assert start < stop # i.e. start <= stop
assert start >= 0
assert stop <= len(content)
self.starts = starts
self.stops = stops
self.content = content
def __len__(self):
return len(self.starts)
def __getitem__(self, where):
if isinstance(where, int):
if where < 0:
where += len(self)
assert 0 <= where < len(self)
return self.content[self.starts[where] : self.stops[where]]
elif isinstance(where, slice) and where.step is None:
starts = self.starts[where.start : where.stop]
stops = self.stops[where.start : where.stop]
return ListArray(starts, stops, self.content)
elif isinstance(where, str):
return ListArray(self.starts, self.stops, self.content[where])
else:
raise AssertionError(where)
- ak.contents.ListArray.starts#
- ak.contents.ListArray.stops#
- ak.contents.ListArray.copy(self, starts=UNSET, stops=UNSET, content=UNSET, *, parameters=UNSET)#
- ak.contents.ListArray.__copy__(self)#
- ak.contents.ListArray.__deepcopy__(self, memo)#
- ak.contents.ListArray.simplified(cls, starts, stops, content, *, parameters=None)#
- ak.contents.ListArray._form_with_key(self, getkey)#
- ak.contents.ListArray._to_buffers(self, form, getkey, container, backend, byteorder)#
- ak.contents.ListArray._to_typetracer(self, forget_length)#
- ak.contents.ListArray._touch_data(self, recursive)#
- ak.contents.ListArray._touch_shape(self, recursive)#
- ak.contents.ListArray.length#
- ak.contents.ListArray.__repr__(self)#
- ak.contents.ListArray._repr(self, indent, pre, post)#
- ak.contents.ListArray.to_ListOffsetArray64(self, start_at_zero=False)#
- ak.contents.ListArray.to_RegularArray(self)#
- ak.contents.ListArray._getitem_nothing(self)#
- ak.contents.ListArray._is_getitem_at_placeholder(self)#
- ak.contents.ListArray._getitem_at(self, where)#
- ak.contents.ListArray._getitem_range(self, start, stop)#
- ak.contents.ListArray._getitem_field(self, where, only_fields=())#
- ak.contents.ListArray._getitem_fields(self, where, only_fields=())#
- ak.contents.ListArray._carry(self, carry, allow_lazy)#
- ak.contents.ListArray._compact_offsets64(self, start_at_zero)#
- ak.contents.ListArray._broadcast_tooffsets64(self, offsets)#
- ak.contents.ListArray._getitem_next_jagged(self, slicestarts, slicestops, slicecontent, tail)#
- ak.contents.ListArray._getitem_next(self, head, tail, advanced)#
- ak.contents.ListArray._offsets_and_flattened(self, axis, depth)#
- ak.contents.ListArray._mergeable_next(self, other, mergebool)#
- ak.contents.ListArray._mergemany(self, others)#
- ak.contents.ListArray._fill_none(self, value)#
- ak.contents.ListArray._local_index(self, axis, depth)#
- ak.contents.ListArray._numbers_to_type(self, name, including_unknown)#
- ak.contents.ListArray._is_unique(self, negaxis, starts, parents, outlength)#
- ak.contents.ListArray._unique(self, negaxis, starts, parents, outlength)#
- ak.contents.ListArray._argsort_next(self, negaxis, starts, shifts, parents, outlength, ascending, stable)#
- ak.contents.ListArray._sort_next(self, negaxis, starts, parents, outlength, ascending, stable)#
- ak.contents.ListArray._combinations(self, n, replacement, recordlookup, parameters, axis, depth)#
- ak.contents.ListArray._reduce_next(self, reducer, negaxis, starts, shifts, parents, outlength, mask, keepdims, behavior)#
- ak.contents.ListArray._validity_error(self, path)#
- ak.contents.ListArray._nbytes_part(self)#
- ak.contents.ListArray._pad_none(self, target, axis, depth, clip)#
- ak.contents.ListArray._to_arrow(self, pyarrow, mask_node, validbytes, length, options)#
- ak.contents.ListArray._to_cudf(self, cudf, mask, length)#
- ak.contents.ListArray._to_backend_array(self, allow_missing, backend)#
- ak.contents.ListArray._remove_structure(self, backend, options)#
- ak.contents.ListArray._drop_none(self)#
- ak.contents.ListArray._rebuild_without_nones(self, none_indexes, new_content)#
- ak.contents.ListArray._recursively_apply(self, action, depth, depth_context, lateral_context, options)#
- ak.contents.ListArray.to_packed(self, recursive=True)#
- ak.contents.ListArray._to_list(self, behavior, json_conversions)#
- ak.contents.ListArray._to_backend(self, backend)#
- ak.contents.ListArray._is_equal_to(self, other, index_dtype, numpyarray, all_parameters)#