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qiskit.circuit.classicalfunction.ClassicalFunction

class ClassicalFunction(source, name=None)

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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

  • ImportError – If tweedledum is not installed.
  • QiskitError – If source is not a string.

__init__

__init__(source, name=None)

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

  • ImportError – If tweedledum is not installed.
  • QiskitError – If source is not a string.

Methods

__init__(source[, name])Creates a ClassicalFunction from Python source code in source.
add_decomposition(decomposition)Add a decomposition of the instruction to the SessionEquivalenceLibrary.
assemble()Assemble a QasmQobjInstruction
broadcast_arguments(qargs, cargs)Validation and handling of the arguments and its relationship.
c_if(classical, val)Add classical condition on register classical and value val.
compile()Parses and creates the logical circuit
control([num_ctrl_qubits, label, ctrl_state])Return controlled version of gate.
copy([name])Copy of the instruction.
inverse()Invert this instruction.
is_parameterized()Return True .IFF.
mirror()DEPRECATED: use instruction.reverse_ops().
power(exponent)Creates a unitary gate as gate^exponent.
qasm()Return a default OpenQASM string for the instruction.
repeat(n)Creates an instruction with gate repeated n amount of times.
reverse_ops()For a composite instruction, reverse the order of sub-instructions.
simulate()Runs tweedledum.simulate on the logic network.
synth([registerless])Synthesis the logic network into a QuantumCircuit.
to_matrix()Return a Numpy.array for the gate unitary matrix.
validate_parameter(parameter)Gate parameters should be int, float, or ParameterExpression

Attributes

argsReturns the classicalfunction arguments
decompositionsGet the decompositions of the instruction from the SessionEquivalenceLibrary.
definitionReturn definition in terms of other basic gates.
durationGet the duration.
labelReturn gate label
networkReturns the logical network
paramsreturn instruction params.
qregsThe list of qregs used by the classicalfunction
scopesReturns the scope dict
typesDumps a list of scopes with their variables and types.
unitGet the time unit of duration.

add_decomposition

add_decomposition(decomposition)

Add a decomposition of the instruction to the SessionEquivalenceLibrary.

args

Returns the classicalfunction arguments

assemble

assemble()

Assemble a QasmQobjInstruction

Return type

Instruction

broadcast_arguments

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

c_if(classical, val)

Add classical condition on register classical and value val.

compile

compile()

Parses and creates the logical circuit

control

control(num_ctrl_qubits=1, label=None, ctrl_state=None)

Return controlled version of gate. See ControlledGate for usage.

Parameters

  • num_ctrl_qubits (Optional[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

qiskit.circuit.ControlledGate

Raises

QiskitError – unrecognized mode or invalid ctrl_state

copy

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

qiskit.circuit.Instruction

decompositions

Get the decompositions of the instruction from the SessionEquivalenceLibrary.

definition

Return definition in terms of other basic gates.

duration

Get the duration.

inverse

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

qiskit.circuit.Instruction

Raises

CircuitError – if the instruction is not composite and an inverse has not been implemented for it.

is_parameterized

is_parameterized()

Return True .IFF. instruction is parameterized else False

label

Return gate label

Return type

str

mirror

mirror()

DEPRECATED: use instruction.reverse_ops().

Returns

a new instruction with sub-instructions

reversed.

Return type

qiskit.circuit.Instruction

network

Returns the logical network

params

return instruction params.

power

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

qiskit.extensions.UnitaryGate

Raises

CircuitError – If Gate is not unitary

qasm

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];).

qregs

The list of qregs used by the classicalfunction

repeat

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

qiskit.circuit.Instruction

Raises

CircuitError – If n < 1.

reverse_ops

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

qiskit.circuit.Instruction

scopes

Returns the scope dict

simulate

simulate()

Runs tweedledum.simulate on the logic network.

synth

synth(registerless=True)

Synthesis the logic network into a QuantumCircuit.

Parameters

  • registerless (bool) – Default True. If False uses the parameter names to create
  • with those names. Otherwise (registers) –
  • a circuit with a flat quantum register. (creates) –

Returns

A circuit implementing the logic network.

Return type

QuantumCircuit

to_matrix

to_matrix()

Return a Numpy.array for the gate unitary matrix.

Raises

CircuitError – If a Gate subclass does not implement this method an exception will be raised when this base class method is called.

Return type

ndarray

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.

validate_parameter

validate_parameter(parameter)

Gate parameters should be int, float, or ParameterExpression

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