sf.lab_dev.wires.Wires

class mrmustard.lab_dev.wires.Wires(modes_out_bra=None, modes_in_bra=None, modes_out_ket=None, modes_in_ket=None)

Bases: object

A class with wire functionality for tensor network applications.

In MrMustard, we represent circuit components as tensors in a tensor network. The wires of these components describe how they connect with the surrounding components. For example, an N-mode pure state has N ket wires on the output side, while a N-mode mixed state has N ket wires and N bra wires on the output side.

Wires objects store the information related to the wires of circuit components. Each wire in a Wires object is specified by a numerical id, which is random and unique. When two different Wires object have one or more wires with the same ids, we treat them as connected. Otherwise, we treat them as disconnected.

The list of all these ids can be accessed using the ids property.

>>> from mrmustard.lab_dev.wires import Wires

>>> modes_out_bra=[0, 1]
>>> modes_in_bra=[1, 2]
>>> modes_out_ket=[0, 3]
>>> modes_in_ket=[1, 2, 3]
>>> w = Wires(modes_out_bra, modes_in_bra, modes_out_ket, modes_in_ket)

>>> # access the modes
>>> modes = w.modes
>>> assert w.modes == [0, 1, 2, 3]

>>> # access the ids
>>> ids = w.ids
>>> assert len(ids) == 9

>>> # get input/output subsets
>>> w_in = w.input
>>> assert w_in.modes == [1, 2, 3]

>>> # get ket/bra subsets
>>> w_in_bra = w_in.bra
>>> assert w_in_bra.modes == [1, 2]

The standard order for the list of ids is:

• ids for all the output bra wires.

• ids for all the input bra wires.

• ids for all the output ket wires.

• ids for all the input ket wires.

>>> assert w.output.bra.ids == w.ids[:2]
>>> assert w.input.bra.ids == w.ids[2:4]
>>> assert w.output.ket.ids == w.ids[4:6]
>>> assert w.input.ket.ids == w.ids[6:]

To access the index of a su set of wires in standard order (i.e. skipping over wires not belonging to the subset), one can use the indices attribute:

>>> w = Wires(modes_in_ket = [0,1], modes_out_ket = [0,1])

>>> assert w.indices == [0,1,2,3]
>>> assert w.input.indices == [2,3]

Note that subsets return new Wires objects with the same ids as the original object.

Parameters:

• modes_out_bra (Optional[Iterable[int]]) – The output modes on the bra side.

• modes_in_bra (Optional[Iterable[int]]) – The input modes on the bra side.

• modes_out_ket (Optional[Iterable[int]]) – The output modes on the ket side.

• modes_in_ket (Optional[Iterable[int]]) – The input modes on the ket side.

Note that the order of the modes passed to initialize the object doesn’t matter, as they get sorted at init time.

Attributes

adjoint	The adjoint of this wires object, obtained by swapping ket and bra wires.
bra	A view of this Wires object without ket wires.
dual	The dual of this wires object, obtained by swapping input and output wires.
id_array	The id_array of the available wires in a two-dimensional array, where line j contains the ids (in the standard order) for mode j.
ids	The list of ids of the available wires in the standard order.
indices	The array of indices of this Wires in the standard order.
input	A view of this Wires object without output wires.
ket	A view of this Wires object without bra wires.
modes	The list of modes of the populated wires.
output	A view of this Wires object without input wires.

adjoint

The adjoint of this wires object, obtained by swapping ket and bra wires.

bra

A view of this Wires object without ket wires.

dual

The dual of this wires object, obtained by swapping input and output wires.

id_array

The id_array of the available wires in a two-dimensional array, where line j contains the ids (in the standard order) for mode j.

ids

The list of ids of the available wires in the standard order.

indices

The array of indices of this Wires in the standard order. The array of indices of this Wires in the standard order. When a subset is selected, it skips the indices of wires that do not belong to the subset.

>>> w = Wires(modes_in_ket = [0,1], modes_out_ket = [0,1])

>>> assert w.indices == [0,1,2,3]
>>> assert w.input.indices == [2,3]

input

A view of this Wires object without output wires.

ket

A view of this Wires object without bra wires.

modes

The list of modes of the populated wires.

output

A view of this Wires object without input wires.

Methods

copy()

A copy of this Wires object, with new ids.

copy()

A copy of this Wires object, with new ids.

Return type:

Wires

code/api/mrmustard.lab_dev.wires.Wires

 

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