RC3XGate
class RC3XGate(label=None)
The simplified 3-controlled Toffoli gate.
The simplified Toffoli gate implements the Toffoli gate up to relative phases. Note, that the simplified Toffoli is not equivalent to the Toffoli. But can be used in places where the Toffoli gate is uncomputed again.
This concrete implementation is from https://arxiv.org/abs/1508.03273, the complete circuit of Fig. 4.
Create a new RC3X gate.
Attributes
decompositions
Get the decompositions of the instruction from the SessionEquivalenceLibrary.
definition
Return definition in terms of other basic gates.
label
Type: str
Return gate label
Return type
str
params
return instruction params.
Methods
add_decomposition
RC3XGate.add_decomposition(decomposition)
Add a decomposition of the instruction to the SessionEquivalenceLibrary.
assemble
broadcast_arguments
RC3XGate.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
RC3XGate.c_if(classical, val)
Add classical condition on register classical and value val.
control
RC3XGate.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
Raises
QiskitError – unrecognized mode or invalid ctrl_state
copy
RC3XGate.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
RC3XGate.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
RC3XGate.is_parameterized()
Return True .IFF. instruction is parameterized else False
mirror
RC3XGate.mirror()
For a composite instruction, reverse the order of sub-gates.
This is done by recursively mirroring all sub-instructions. It does not invert any gate.
Returns
a fresh gate with sub-gates reversed
Return type
power
RC3XGate.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
RC3XGate.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
RC3XGate.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.
to_matrix
RC3XGate.to_matrix()
Return a numpy.array for the RC3X gate.