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Applies arithmetic to a target and some inputs.
Inherits From: ArithmeticGate
, Gate
cirq.interop.quirk.QuirkArithmeticGate(
identifier: str,
target: Sequence[int],
inputs: Sequence[Union[Sequence[int], int]]
)
Implements Quirkspecific implicit effects like assuming that the presence of an 'r' input implies modular arithmetic.
In Quirk, modular operations have no effect on values larger than the modulus. This convention is used because unitarity forces some convention on outofrange values (they cannot simply disappear or raise exceptions), and the simplest is to do nothing. This call handles ensuring that happens, and ensuring the new target register value is normalized modulo the modulus.
Args  

identifier

The quirk identifier string for this operation. 
target

The target qubit register. 
inputs

Qubit registers, which correspond to the qid shape of the qubits from which the input will be read, or classical constants, that determine what happens to the target. 
Raises  

ValueError

If the target is too small for a modular operation with too small modulus. 
Attributes  

operation

Methods
apply
apply(
*registers
) > Union[int, Iterable[int]]
Returns the result of the gate operating on classical values.
For example, an addition takes two values (the target and the source), adds the source into the target, then returns the target and source as the new register values.
The apply
method is permitted to be sloppy in three ways:
 The
apply
method is permitted to return values that have more bits than the registers they will be stored into. The extra bits are simply dropped. For example, if the value 5 is returned for a 2 qubit register then 5 % 22 = 1 will be used instead. Negative values are also permitted. For example, for a 3 qubit register the value 2 becomes 2 % 23 = 6.  When the value of the last
k
registers is not changed by the gate, theapply
method is permitted to omit these values from the result. That is to say, when the length of the output is less than the length of the input, it is padded up to the intended length by copying from the same position in the input.  When only the first register's value changes, the
apply
method is permitted to return anint
instead of a sequence of ints.
The apply
method must be reversible. Otherwise the gate will
not be unitary, and incorrect behavior will result.
Examples:
A fully detailed adder:
def apply(self, target, offset):
return (target + offset) % 2**len(self.target_register), offset
The same adder, with less boilerplate due to the details being
handled by the ArithmeticGate
class:
def apply(self, target, offset):
return target + offset
controlled
controlled(
num_controls: int = None,
control_values: Optional[Sequence[Union[int, Collection[int]]]] = None,
control_qid_shape: Optional[Tuple[int, ...]] = None
) > 'Gate'
Returns a controlled version of this gate. If no arguments are specified, defaults to a single qubit control.
num_controls: Total number of control qubits.
control_values: For which control qubit values to apply the sub
gate. A sequence of length num_controls
where each
entry is an integer (or set of integers) corresponding to the
qubit value (or set of possible values) where that control is
enabled. When all controls are enabled, the sub gate is
applied. If unspecified, control values default to 1.
control_qid_shape: The qid shape of the controls. A tuple of the
expected dimension of each control qid. Defaults to
(2,) * num_controls
. Specify this argument when using qudits.
num_qubits
num_qubits() > int
The number of qubits this gate acts on.
on
on(
*qubits
) > 'Operation'
Returns an application of this gate to the given qubits.
Args  

*qubits

The collection of qubits to potentially apply the gate to. 
on_each
on_each(
*targets
) > List['cirq.Operation']
Returns a list of operations applying the gate to all targets.
Args  

*targets

The qubits to apply this gate to. For singlequbit gates
this can be provided as varargs or a combination of nested
iterables. For multiqubit gates this must be provided as an
Iterable[Sequence[Qid]] , where each sequence has num_qubits
qubits.

Returns  

Operations applying this gate to the target qubits. 
Raises  

ValueError

If targets are not instances of Qid or Iterable[Qid]. If the gate qubit number is incompatible. 
TypeError

If a single target is supplied and it is not iterable. 
registers
registers() > Sequence[Union[int, Sequence[int]]]
The data acted upon by the arithmetic gate.
Each register in the list can either be a classical constant (an int
),
or else a list of qubit/qudit dimensions. Registers that are set to a
classical constant must not be mutated by the arithmetic gate
(their value must remain fixed when passed to apply
).
Registers are big endian. The first qubit is the most significant, the last qubit is the 1s qubit, the before last qubit is the 2s qubit, etc.
Returns  

A list of constants and qubit groups that the gate will act upon. 
validate_args
validate_args(
qubits: Sequence['cirq.Qid']
) > None
Checks if this gate can be applied to the given qubits.
By default checks that:
 inputs are of type
Qid
 len(qubits) == num_qubits()
 qubit_i.dimension == qid_shape[i] for all qubits
Child classes can override. The child implementation should call
super().validate_args(qubits)
then do custom checks.
Args  

qubits

The sequence of qubits to potentially apply the gate to. 
Throws:
ValueError
: The gate can't be applied to the qubits.
with_probability
with_probability(
probability: 'cirq.TParamVal'
) > 'cirq.Gate'
with_registers
with_registers(
*new_registers
) > 'QuirkArithmeticGate'
Returns the same fate targeting different registers.
Args  

*new_registers

The new values that should be returned by the
registers method.

Returns  

An instance of the same kind of gate, but acting on different registers. 
wrap_in_linear_combination
wrap_in_linear_combination(
coefficient: Union[complex, float, int] = 1
) > 'cirq.LinearCombinationOfGates'
__add__
__add__(
other: Union['Gate', 'cirq.LinearCombinationOfGates']
) > 'cirq.LinearCombinationOfGates'
__call__
__call__(
*qubits, **kwargs
)
Call self as a function.
__eq__
__eq__(
other: _SupportsValueEquality
) > bool
__mul__
__mul__(
other: Union[complex, float, int]
) > 'cirq.LinearCombinationOfGates'
__ne__
__ne__(
other: _SupportsValueEquality
) > bool
__neg__
__neg__() > 'cirq.LinearCombinationOfGates'
__pow__
__pow__(
power
)
__rmul__
__rmul__(
other: Union[complex, float, int]
) > 'cirq.LinearCombinationOfGates'
__sub__
__sub__(
other: Union['Gate', 'cirq.LinearCombinationOfGates']
) > 'cirq.LinearCombinationOfGates'
__truediv__
__truediv__(
other: Union[complex, float, int]
) > 'cirq.LinearCombinationOfGates'