Circuits tokenizer

Class to tokenize quantum circuits. Encode and decode quantum circuits into and from tensor representations.

CircuitTokenizer


def CircuitTokenizer(
    vocabulary:dict[str, int] | dict[typing.Any, int], sign_labels:Optional=None
)->None:

Helper class that provides a standard way to create an ABC using inheritance.

Test

tensor = torch.tensor([
                [1, 0,-2],
                [0, 1, 2],
                [0, 0,-2],
            ], dtype=torch.int32)

params_tensor = torch.tensor([       # ... [max_params, time]
                    [-0.9,  0.9, 0],
                    [ 0.1, -0.7, 0]
                ])

tokenizer    = CircuitTokenizer({"u2":1, "ccx":2})
instructions = tokenizer.decode(tensor, params_tensor)

instructions.print()
print(instructions.instruction_names_set)

CircuitInstruction(name='u2', control_nodes=[], target_nodes=[0], params=[0.628318727016449, 6.91150426864624])
CircuitInstruction(name='u2', control_nodes=[], target_nodes=[1], params=[11.9380521774292, 1.8849557638168335])
CircuitInstruction(name='ccx', control_nodes=[0, 2], target_nodes=[1], params=[6.2831854820251465, 6.2831854820251465])
{'u2', 'ccx'}

enc_tensor, enc_params_tensor = tokenizer.encode(instructions)
enc_tensor, enc_params_tensor

(tensor([[ 1,  0, -2],
         [ 0,  1,  2],
         [ 0,  0, -2]], dtype=torch.int32),
 tensor([[-0.9000,  0.9000,  0.0000],
         [ 0.1000, -0.7000,  0.0000]]))

assert torch.allclose(tensor, enc_tensor)
assert torch.allclose(params_tensor, enc_params_tensor)

tokenizer = CircuitTokenizer({"u2":1, "ccx":2})
assert tokenizer.vocabulary == {'u2': 1, 'ccx': 2}

# test background token checking
tokenizer = CircuitTokenizer({"u2":0, "ccx":1, "h":2, "ry":3})
assert tokenizer.vocabulary == {"u2":1, "ccx":2, "h":3, "ry":4}

[WARNING]: The value 0 is reserved for background tokens, i.e. qubit time position which are not effected by gates.
[WARNING]: Automatically incrementing all vocabulary values by one ...

print(CircuitTokenizer.get_parametrized_tokens(tokenizer.vocabulary))
assert CircuitTokenizer.get_parametrized_tokens(tokenizer.vocabulary) == [1, 4]

[1, 4]