HamiltonianGate
class HamiltonianGate(data, time, label=None)
Bases: qiskit.circuit.gate.Gate
Class for representing evolution by a Hermitian Hamiltonian operator as a gate. This gate resolves to a UnitaryGate U(t) = exp(-1j * t * H), which can be decomposed into basis gates if it is 2 qubits or less, or simulated directly in Aer for more qubits.
Create a gate from a hamiltonian operator and evolution time parameter t
Parameters
- data (matrix or Operator) – a hermitian operator.
- time (float) – time evolution parameter.
- label (str) – unitary name for backend [Default: None].
Raises
ExtensionError – if input data is not an N-qubit unitary operator.
Methods
add_decomposition
HamiltonianGate.add_decomposition(decomposition)
Add a decomposition of the instruction to the SessionEquivalenceLibrary.
adjoint
HamiltonianGate.adjoint()
Return the adjoint of the unitary.
assemble
HamiltonianGate.assemble()
Assemble a QasmQobjInstruction
broadcast_arguments
HamiltonianGate.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
HamiltonianGate.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
HamiltonianGate.conjugate()
Return the conjugate of the Hamiltonian.
control
HamiltonianGate.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
[str
,int
,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
HamiltonianGate.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
HamiltonianGate.inverse()
Return the adjoint of the unitary.
is_parameterized
HamiltonianGate.is_parameterized()
Return True .IFF. instruction is parameterized else False
power
HamiltonianGate.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
HamiltonianGate.qasm()
Raise an error, as QASM is not defined for the HamiltonianGate.
repeat
HamiltonianGate.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
HamiltonianGate.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
HamiltonianGate.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
HamiltonianGate.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
HamiltonianGate.transpose()
Return the transpose of the Hamiltonian.
validate_parameter
HamiltonianGate.validate_parameter(parameter)
Hamiltonian parameter has to be an ndarray, operator or float.
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.