SwapGate
SwapGate(label=None)
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The SWAP gate.
This is a symmetric and Clifford gate.
Circuit symbol:
q_0: ─X─
│
q_1: ─X─
Matrix Representation:
The gate is equivalent to a state swap and is a classical logic gate.
Create new SWAP gate.
Attributes
decompositions
Get the decompositions of the instruction from the SessionEquivalenceLibrary.
definition
Return definition in terms of other basic gates.
label
str
Return gate label
Return type
str
params
return instruction params.
Methods
add_decomposition
SwapGate.add_decomposition(decomposition)
Add a decomposition of the instruction to the SessionEquivalenceLibrary.
assemble
SwapGate.assemble()
Assemble a QasmQobjInstruction
Return type
broadcast_arguments
SwapGate.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
SwapGate.c_if(classical, val)
Add classical condition on register classical and value val.
control
SwapGate.control(num_ctrl_qubits=1, label=None, ctrl_state=None)
Return a (multi-)controlled-SWAP gate.
One control returns a CSWAP (Fredkin) gate.
Parameters
- num_ctrl_qubits (int) – number of control qubits.
- label (str or None) – An optional label for the gate [Default: None]
- ctrl_state (int or str or None) – control state expressed as integer, string (e.g. ‘110’), or None. If None, use all 1s.
Returns
controlled version of this gate.
Return type
copy
SwapGate.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
SwapGate.inverse()
Return inverse Swap gate (itself).
is_parameterized
SwapGate.is_parameterized()
Return True .IFF. instruction is parameterized else False
mirror
SwapGate.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
SwapGate.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
SwapGate.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
SwapGate.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
SwapGate.to_matrix()
Return a numpy.array for the SWAP gate.