OperatorStateFn¶
- class OperatorStateFn(primitive, coeff=1.0, is_measurement=False)[source]¶
Bases:
qiskit.opflow.state_fns.state_fn.StateFn
A class for state functions and measurements which are defined by a density Operator, stored using an
OperatorBase
.- Parameters
primitive (
OperatorBase
) – TheOperatorBase
which defines the behavior of the underlying State function.coeff (
Union
[complex
,ParameterExpression
]) – A coefficient by which to multiply the state functionis_measurement (
bool
) – Whether the StateFn is a measurement operator
Methods Defined Here
Return Operator addition of self and other, overloaded by
+
.Return a new Operator equal to the Operator's adjoint (conjugate transpose), overloaded by
~
.Evaluate the Operator's underlying function, either on a binary string or another Operator.
Permute the qubits of the state function.
Return a set of strings describing the primitives contained in the Operator.
Sample the state function as a normalized probability distribution.
Return tensor product between self and other, overloaded by
^
.Return
StateFnCircuit
corresponding to this StateFn.Return numpy matrix of density operator, warn if more than 16 qubits to force the user to set massive=True if they want such a large matrix.
Note: this does not return a density matrix, it returns a classical matrix containing the quantum or classical vector representing the evaluation of the state function on each binary basis state.
Return a MatrixOp for this operator.
Attributes
- INDENTATION = ' '¶
- coeff¶
A coefficient by which the state function is multiplied.
- Return type
Union
[complex
,ParameterExpression
]
- instance_id¶
Return the unique instance id.
- Return type
int
- is_measurement¶
Whether the StateFn object is a measurement Operator.
- Return type
bool
- num_qubits¶
- Return type
int
- parameters¶
- primitive: qiskit.opflow.operator_base.OperatorBase¶
The primitive which defines the behavior of the underlying State function.
- settings¶
Return settings.
- Return type
Dict