ak.firsts¶
Defined in awkward.operations.structure on line 3014.
- ak.firsts(array, axis=1, highlevel=True, behavior=None)¶
- Parameters
array – Data from which to select the first elements from nested lists.
axis (int) – The dimension at which this operation is applied. The outermost dimension is
0
, followed by1
, etc., and negative values count backward from the innermost:-1
is the innermost dimension,-2
is the next level up, etc.highlevel (bool) – If True, return an
ak.Array
; otherwise, return a low-levelak.layout.Content
subclass.behavior (None or dict) – Custom
ak.behavior
for the output array, if high-level.
Selects the first element of each non-empty list and inserts None for each empty list.
For example,
>>> array = ak.Array([[1.1], [2.2], [], [3.3], [], [], [4.4], [5.5]])
>>> print(ak.firsts(array))
[1.1, 2.2, None, 3.3, None, None, 4.4, 5.5]
See ak.singletons
to invert this function.