ak.layout.Content¶

Superclass of array nodes that build up the structure of an ak.Array; the array layout returned by the ak.Array.layout property.

The array node types are listed below.

ak.layout.EmptyArray: array with zero length and ak.types.UnknownType.

ak.layout.NumpyArray: complete equivalent to a NumPy np.ndarray, usually with ak.types.PrimitiveType.

ak.layout.RegularArray: nested lists of equal length; has ak.types.RegularType.

ak.layout.ListArray (64-bit, 32-bit, and unsigned 32-bit specializations): nested lists of any length (built with two indexes, starts and stops), has ak.types.ListType.

ak.layout.ListOffsetArray (64-bit, 32-bit, and unsigned 32-bit specializations): nested lists of any length (built with one index, offsets), has ak.types.ListType.

ak.layout.RecordArray: array of records or tuples; has ak.types.RecordType.

ak.layout.IndexedArray (64-bit, 32-bit, and unsigned 32-bit specializations): contains any array and reorders/duplicates it with an arbitrary integer index; has the same type as its content.

ak.layout.IndexedOptionArray (64-bit and 32-bit specializations): same as above but -1 values in the index are interpreted as None; has ak.types.OptionType.

ak.layout.ByteMaskedArray: boolean bytes in a mask are interpreted as valid contents or None; has ak.types.OptionType.

ak.layout.BitMaskedArray: boolean bits in a mask are interpreted as valid contents or None; has ak.types.OptionType.

ak.layout.UnmaskedArray: formally has ak.types.OptionType, but all data are valid (no mask).

ak.layout.UnionArray (8-bit signed tags with 64-bit, 32-bit, and unsigned 32-bit index specializations): heterogeneous data represented as a tagged union; has ak.types.UnionType.

In Python, ak.layout.Record is not a subclass of ak.layout.Content (though it is in C++ for technical reasons).

All ak.layout.Content nodes have the following properties and methods in common.

ak.layout.Content.identities¶

ak.layout.Content.identities¶

Returns the ak.layout.Identities object associated with this array node (if any).

ak.layout.Content.identity¶

ak.layout.Content.identity¶

Returns the single element of an ak.layout.Identities associated with this array node (if any).

ak.layout.Content.nbytes¶

ak.layout.Content.nbytes¶

The total number of bytes in all the ak.layout.Index, ak.layout.Identities, and ak.layout.NumpyArray buffers in this array tree.

Note: this calculation takes overlapping buffers into account, to the extent that overlaps are not double-counted, but overlaps are currently assumed to be complete subsets of one another, and so it is theoretically possible (though unlikely) that this number is an underestimate of the true usage.

It also does not count buffers that must be kept in memory because of ownership, but are not directly used in the array. Nor does it count the (small) C++ nodes or Python objects that reference the (large) array buffers.

ak.layout.Content.numfields¶

ak.layout.Content.numfields¶

Number of fields in the outermost records or tuples, or -1 if the array does not contain records or tuples.

ak.layout.Content.parameters¶

ak.layout.Content.parameters¶

Free-form parameters associated with every array node as a dict from parameter name to its JSON-like value. Some parameters are special and are used to assign behaviors to the data.

Note that the dict returned by this property is a copy of the array node’s parameters. Changing the dict will not change the array!

See ak.behavior and ak.Array.

ak.layout.Content.purelist_depth¶

ak.layout.Content.purelist_depth¶

Number of dimensions of nested lists, not counting anything deeper than the first record or tuple layer, if any. The depth of a one-dimensional array is 1.

If the array contains ak.types.UnionType data and its contents have equal depths, the return value is that depth. If they do not have equal depths, the return value is -1.

ak.layout.Content.purelist_isregular¶

ak.layout.Content.purelist_isregular¶

Returns True if all dimensions down to the first record or tuple layer have ak.types.RegularType; False otherwise.

ak.layout.Content.getitem¶

ak.layout.Content.__getitem__(where)¶

See ak.Array.__getitem__.

ak.layout.Content.iter¶

ak.layout.Content.__iter__()¶

See ak.Array.__iter__.

ak.layout.Content.len¶

ak.layout.Content.__len__()¶

See ak.Array.__len__.

ak.layout.Content.repr¶

ak.layout.Content.__repr__()¶

A multi-line XML representation of the array structure.

See (for contrast) ak.Array.__repr__.

ak.layout.Content.all¶

ak.layout.Content.all(axis=- 1, mask=False, keepdims=False)¶

Implements ak.all.

ak.layout.Content.any¶

ak.layout.Content.any(axis=- 1, mask=False, keepdims=False)¶

Implements ak.any.

ak.layout.Content.argmax¶

ak.layout.Content.argmax(axis=- 1, mask=True, keepdims=False)¶

Implements ak.argmax.

ak.layout.Content.argmin¶

ak.layout.Content.argmin(axis=- 1, mask=True, keepdims=False)¶

Implements ak.argmin.

ak.layout.Content.combinations¶

ak.layout.Content.combinations(n, replacement=False, keys=None, parameters=None, axis=1)¶

Implements ak.combinations.

ak.layout.Content.count¶

ak.layout.Content.count(axis=- 1, mask=False, keepdims=False)¶

Implements ak.count.

ak.layout.Content.count_nonzero¶

ak.layout.Content.count_nonzero(axis=- 1, mask=False, keepdims=False)¶

Implements ak.count_nonzero.

ak.layout.Content.deep_copy¶

ak.layout.Content.deep_copy(copyarrays=True, copyindexes=True, copyidentities=True)¶

Returns a copy of the array node and its children.

If copyarrays, then ak.layout.NumpyArray buffers are also copied.

If copyindexes, then ak.layout.Index buffers are also copied.

If copyidentities, then ak.layout.Identities buffers are also copied.

If all three flags are False, then only (small) C++ and Pyhton objects are copied, not (large) array buffers.

ak.layout.Content.fieldindex¶

ak.layout.Content.fieldindex(key)¶

Returns the fieldindex (int) associated with a key (str) of the outermost record or tuple. If the array does not contain records or tuples, this method raises an error.

ak.layout.Content.fillna¶

ak.layout.Content.fillna(value)¶

Implements ak.fill_none.

ak.layout.Content.flatten¶

ak.layout.Content.flatten(axis=1)¶

Implements ak.flatten.

ak.layout.Content.getitem_nothing¶

ak.layout.Content.getitem_nothing()¶

Returns an empty array with this array structure. Used for a corner-case of __getitem__.

ak.layout.Content.haskey¶

ak.layout.Content.haskey(key)¶

Returns True if the outermost record or tuple has a given key; False otherwise (including the case of not containing records or tuples).

ak.layout.Content.key¶

ak.layout.Content.key(fieldindex)¶

Returns the key (str) associated with a fieldindex (int) of the outermost record or tuple. If the array does not contain records or tuples, this method raises an error.

ak.layout.Content.keys¶

ak.layout.Content.keys()¶

Returns the keys of the outermost record or tuple or an empty list.

ak.layout.Content.localindex¶

ak.layout.Content.localindex(axis=1)¶

Returns nested lists of integers (down to the chosen axis) that count from 0 to the length - 1 of the innermost list.

This is used internally to generate ak.argcartesian from ak.cartesian, etc.

ak.layout.Content.max¶

ak.layout.Content.max(axis=- 1, mask=True, keepdims=False)¶

Implements ak.max.

ak.layout.Content.merge¶

ak.layout.Content.merge(other)¶

Concatenate this array node with the other array node (axis=0) by sharing buffers; i.e. without using a ak.layout.UnionArray. If this is not possible, this method raises an error.

ak.layout.Content.merge_as_union¶

ak.layout.Content.merge_as_union(other)¶

Concatenate this array node with the other array node (axis=0) using a ak.layout.UnionArray instead of attempting to share buffers.

ak.layout.Content.mergeable¶

ak.layout.Content.mergeable(other, mergebool=False)¶

If True, this array node can be concatenated (axis=0) with the other array node without resorting to a ak.layout.UnionArray; otherwise, they cannot.

If mergebool is True, consider booleans to be a numeric type that can be merged with numeric arrays (integers and floating-point).

ak.layout.Content.min¶

ak.layout.Content.min(axis=- 1, mask=True, keepdims=False)¶

Implements ak.min.

ak.layout.Content.num¶

ak.layout.Content.num(axis=1)¶

Implements ak.num.

ak.layout.Content.offsets_and_flatten¶

ak.layout.Content.offsets_and_flatten(axis=1)¶

Implements ak.flatten, though it returns a set of offsets along with the flattened array.

ak.layout.Content.parameter¶

ak.layout.Content.parameter(key)¶

Get one parameter by its key (outermost node only). If a key is not found, None is returned.

ak.layout.Content.prod¶

ak.layout.Content.prod(axis=- 1, mask=False, keepdims=False)¶

Implements ak.prod.

ak.layout.Content.purelist_parameter¶

ak.layout.Content.purelist_parameter(key)¶

Return the value of the outermost parameter matching key in a sequence of nested lists, stopping at the first record or tuple layer.

If a layer has ak.types.UnionType, the value is only returned if all possibilities have the same value.

ak.layout.Content.rpad¶

ak.layout.Content.rpad(arg0, arg1)¶

Implements ak.pad_none with clip=False.

ak.layout.Content.rpad_and_clip¶

ak.layout.Content.rpad_and_clip(arg0, arg1)¶

Implements ak.pad_none with clip=True.

ak.layout.Content.setidentities¶

ak.layout.Content.setidentities()¶

ak.layout.Content.setidentities(identities)¶

Sets identities in-place.

Do not use this function: it is deprecated and will be removed. Assign ak.layout.Identities in the constructor only.

ak.layout.Content.setparameter¶

ak.layout.Content.setparameter(key, value)¶

Sets one parameter in-place.

Do not use this function: it is deprecated and will be removed. Assign parameters in the constructor only.

ak.layout.Content.simplify¶

ak.layout.Content.simplify()¶

Flattens one extraneous level of ak.types.OptionType or ak.types.UnionType. If there is no such level, this is a pass-through. In all cases, the output has the same logical meaning as the input.

ak.layout.Content.sum¶

ak.layout.Content.sum(axis=- 1, mask=False, keepdims=False)¶

Implements ak.sum.

ak.layout.Content.toRegularArray¶

ak.layout.Content.toRegularArray()¶

Converts the data to a ak.layout.RegularArray, if possible.

ak.layout.Content.tojson¶

ak.layout.Content.tojson(pretty=False, maxdecimals=None)¶

Converts this array node to JSON and returns it as a string.

See ak.to_json.

ak.layout.Content.tojson(destination, pretty=False, maxdecimals=None, buffersize=65536)¶

Converts this array node to JSON and writes it to a file (destination).