ClassicalFunction
class ClassicalFunction(source, name=None)
Bases: qiskit.circuit.classicalfunction.classical_element.ClassicalElement
Represent a classical function function and its logic network.
Creates a ClassicalFunction from Python source code in source.
The code should be a single function with types.
Parameters
- source (str) – Python code with type hints.
- name (str) – Optional. Default: “classicalfunction”. ClassicalFunction name.
Raises
QiskitError – If source is not a string.
Methods
add_decomposition
ClassicalFunction.add_decomposition(decomposition)
Add a decomposition of the instruction to the SessionEquivalenceLibrary.
assemble
ClassicalFunction.assemble()
Assemble a QasmQobjInstruction
broadcast_arguments
ClassicalFunction.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
ClassicalFunction.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.
compile
ClassicalFunction.compile()
Parses and creates the logical circuit
control
ClassicalFunction.control(num_ctrl_qubits=1, label=None, ctrl_state=None)
Return controlled version of gate. See ControlledGate for usage.
Parameters
- num_ctrl_qubits (
int) – number of controls to add to gate (default=1) - label (
Optional[str]) – optional gate label - ctrl_state (
Union[int,str,None]) – The control state in decimal or as a bitstring (e.g. ‘111’). If None, use 2**num_ctrl_qubits-1.
Returns
Controlled version of gate. This default algorithm uses num_ctrl_qubits-1 ancillae qubits so returns a gate of size num_qubits + 2*num_ctrl_qubits - 1.
Return type
Raises
QiskitError – unrecognized mode or invalid ctrl_state
copy
ClassicalFunction.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
ClassicalFunction.inverse()
Invert this instruction.
If the instruction is composite (i.e. has a definition), then its definition will be recursively inverted.
Special instructions inheriting from Instruction can implement their own inverse (e.g. T and Tdg, Barrier, etc.)
Returns
a fresh instruction for the inverse
Return type
Raises
CircuitError – if the instruction is not composite and an inverse has not been implemented for it.
is_parameterized
ClassicalFunction.is_parameterized()
Return True .IFF. instruction is parameterized else False
power
ClassicalFunction.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
ClassicalFunction.qasm()
Return a default OpenQASM string for the instruction.
Derived instructions may override this to print in a different format (e.g. measure q[0] -> c[0];).
repeat
ClassicalFunction.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
ClassicalFunction.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
simulate
ClassicalFunction.simulate(bitstring)
Evaluate the expression on a bitstring.
This evaluation is done classically.
Parameters
bitstring (str) – The bitstring for which to evaluate.
Returns
result of the evaluation.
Return type
bool
simulate_all
ClassicalFunction.simulate_all()
Returns a truth table.
Returns
a bitstring with a truth table
Return type
str
soft_compare
ClassicalFunction.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
synth
ClassicalFunction.synth(registerless=True, synthesizer=None)
Synthesis the logic network into a QuantumCircuit.
Parameters
- registerless (
bool) – DefaultTrue. IfFalseuses the parameter names to create - with those names. Otherwise (registers) –
- a circuit with a flat quantum register. (creates) –
- synthesizer (
Optional[Callable[[ClassicalElement],QuantumCircuit]]) – Optional. If None tweedledum’s pkrm_synth is used.
Returns
A circuit implementing the logic network.
Return type
to_matrix
ClassicalFunction.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.
validate_parameter
ClassicalFunction.validate_parameter(parameter)
Gate parameters should be int, float, or ParameterExpression
Attributes
args
Returns the classicalfunction arguments
condition_bits
Get Clbits in condition.
Return type
List[Clbit]
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.
network
Returns the logical network
num_clbits
Return the number of clbits.
num_qubits
Return the number of qubits.
params
return instruction params.
qregs
The list of qregs used by the classicalfunction
scopes
Returns the scope dict
truth_table
Returns (and computes) the truth table
types
Dumps a list of scopes with their variables and types.
Returns
A list of scopes as dicts, where key is the variable name and value is its type.
Return type
list(dict)
unit
Get the time unit of duration.