ak.firsts — Awkward Array 2.8.2 documentation (original) (raw)

Defined in awkward.operations.ak_firsts on line 25.

ak.firsts(array, axis=1, *, highlevel=True, behavior=None, attrs=None)#

Parameters:

• array – Array-like data (anything ak.to_layout recognizes).
• axis (int) – The dimension at which this operation is applied. The outermost dimension is 0, followed by 1, 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-level ak.contents.Content subclass.
• behavior (None or dict) – Custom ak.behavior for the output array, if high-level.
• attrs (None or dict) – Custom attributes 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]]) ak.firsts(array).show() [1.1, 2.2, None, 3.3, None, None, 4.4, 5.5]

See ak.singletons to invert this function.