Defined in awkward.operations.describe on line 78.


The high-level type of an array (many types supported, including all Awkward Arrays and Records) as ak.types.Type objects.

The high-level type ignores #layout differences like ak.layout.ListArray64 versus ak.layout.ListOffsetArray64, but not differences like “regular-sized lists” (i.e. ak.layout.RegularArray) versus “variable-sized lists” (i.e. ak.layout.ListArray64 and similar).

Types are rendered as Datashape strings, which makes the same distinctions.

For example,

ak.Array([[{"x": 1.1, "y": [1]}, {"x": 2.2, "y": [2, 2]}],
          [{"x": 3.3, "y": [3, 3, 3]}]])

has type

3 * var * {"x": float64, "y": var * int64}


ak.Array(np.arange(2*3*5).reshape(2, 3, 5))

has type

2 * 3 * 5 * int64

Some cases, like heterogeneous data, require extensions beyond the Datashape specification. For example,

ak.Array([1, "two", [3, 3, 3]])

has type

3 * union[int64, string, var * int64]

but “union” is not a Datashape type-constructor. (Its syntax is similar to existing type-constructors, so it’s a plausible addition to the language.)