UnitaryGate
class UnitaryGate(data, label=None)
Bases: qiskit.circuit.gate.Gate
Class quantum gates specified by a unitary matrix.
Example
We can create a unitary gate from a unitary matrix then add it to a quantum circuit. The matrix can also be directly applied to the quantum circuit, see unitary().
from qiskit import QuantumCircuit
from qiskit.extensions import UnitaryGate
matrix = [[0, 0, 0, 1],
[0, 0, 1, 0],
[1, 0, 0, 0],
[0, 1, 0, 0]]
gate = UnitaryGate(matrix)
circuit = QuantumCircuit(2)
circuit.append(gate, [0, 1])Create a gate from a numeric unitary matrix.
Parameters
- data (matrix or Operator) – unitary operator.
- label (str) – unitary name for backend [Default: None].
Raises
ExtensionError – if input data is not an N-qubit unitary operator.
Methods
add_decomposition
UnitaryGate.add_decomposition(decomposition)
Add a decomposition of the instruction to the SessionEquivalenceLibrary.
adjoint
UnitaryGate.adjoint()
Return the adjoint of the unitary.
assemble
UnitaryGate.assemble()
Assemble a QasmQobjInstruction
broadcast_arguments
UnitaryGate.broadcast_arguments(qargs, cargs)
Validation and handling of the arguments and its relationship.
For example, cx([q[0],q[1]], q[2]) means cx(q[0], q[2]); cx(q[1], q[2]). This method yields the arguments in the right grouping. In the given example:
in: [[q[0],q[1]], q[2]],[]
outs: [q[0], q[2]], []
[q[1], q[2]], []The general broadcasting rules are:
If len(qargs) == 1:
[q[0], q[1]] -> [q[0]],[q[1]]If len(qargs) == 2:
[[q[0], q[1]], [r[0], r[1]]] -> [q[0], r[0]], [q[1], r[1]] [[q[0]], [r[0], r[1]]] -> [q[0], r[0]], [q[0], r[1]] [[q[0], q[1]], [r[0]]] -> [q[0], r[0]], [q[1], r[0]]If len(qargs) >= 3:
[q[0], q[1]], [r[0], r[1]], ...] -> [q[0], r[0], ...], [q[1], r[1], ...]
Parameters
- qargs (
List) – List of quantum bit arguments. - cargs (
List) – List of classical bit arguments.
Return type
Tuple[List, List]
Returns
A tuple with single arguments.
Raises
CircuitError – If the input is not valid. For example, the number of arguments does not match the gate expectation.
c_if
UnitaryGate.c_if(classical, val)
Set a classical equality condition on this instruction between the register or cbit classical and value val.
This is a setter method, not an additive one. Calling this multiple times will silently override any previously set condition; it does not stack.
conjugate
UnitaryGate.conjugate()
Return the conjugate of the unitary.
control
UnitaryGate.control(num_ctrl_qubits=1, label=None, ctrl_state=None)
Return controlled version of gate
Parameters
- num_ctrl_qubits (int) – number of controls to add to gate (default=1)
- label (str) – optional gate label
- ctrl_state (int or str or None) – The control state in decimal or as a bit string (e.g. ‘1011’). If None, use 2**num_ctrl_qubits-1.
Returns
controlled version of gate.
Return type
Raises
- QiskitError – Invalid ctrl_state.
- ExtensionError – Non-unitary controlled unitary.
copy
UnitaryGate.copy(name=None)
Copy of the instruction.
Parameters
name (str) – name to be given to the copied circuit, if None then the name stays the same.
Returns
a copy of the current instruction, with the name
updated if it was provided
Return type
inverse
UnitaryGate.inverse()
Return the adjoint of the unitary.
is_parameterized
UnitaryGate.is_parameterized()
Return True .IFF. instruction is parameterized else False
power
UnitaryGate.power(exponent)
Creates a unitary gate as gate^exponent.
Parameters
exponent (float) – Gate^exponent
Returns
To which to_matrix is self.to_matrix^exponent.
Return type
Raises
CircuitError – If Gate is not unitary
qasm
UnitaryGate.qasm()
The qasm for a custom unitary gate This is achieved by adding a custom gate that corresponds to the definition of this gate. It gives the gate a random name if one hasn’t been given to it.
repeat
UnitaryGate.repeat(n)
Creates an instruction with gate repeated n amount of times.
Parameters
n (int) – Number of times to repeat the instruction
Returns
Containing the definition.
Return type
Raises
CircuitError – If n < 1.
reverse_ops
UnitaryGate.reverse_ops()
For a composite instruction, reverse the order of sub-instructions.
This is done by recursively reversing all sub-instructions. It does not invert any gate.
Returns
a new instruction with
sub-instructions reversed.
Return type
soft_compare
UnitaryGate.soft_compare(other)
Soft comparison between gates. Their names, number of qubits, and classical bit numbers must match. The number of parameters must match. Each parameter is compared. If one is a ParameterExpression then it is not taken into account.
Parameters
other (instruction) – other instruction.
Returns
are self and other equal up to parameter expressions.
Return type
bool
to_matrix
UnitaryGate.to_matrix()
Return a Numpy.array for the gate unitary matrix.
Returns
if the Gate subclass has a matrix definition.
Return type
np.ndarray
Raises
CircuitError – If a Gate subclass does not implement this method an exception will be raised when this base class method is called.
transpose
UnitaryGate.transpose()
Return the transpose of the unitary.
validate_parameter
UnitaryGate.validate_parameter(parameter)
Unitary gate parameter has to be an ndarray.
Attributes
condition_bits
decompositions
Get the decompositions of the instruction from the SessionEquivalenceLibrary.
definition
Return definition in terms of other basic gates.
duration
Get the duration.
label
Return instruction label
Return type
str
name
Return the name.
num_clbits
Return the number of clbits.
num_qubits
Return the number of qubits.
params
return instruction params.
unit
Get the time unit of duration.