PrimitiveOp

class PrimitiveOp(primitive, coeff=1.0)

Bases: qiskit.opflow.operator_base.OperatorBase

A class for representing basic Operators, backed by Operator primitives from Terra. This class (and inheritors) primarily serves to allow the underlying primitives to “flow” - i.e. interoperability and adherence to the Operator formalism - while the core computational logic mostly remains in the underlying primitives. For example, we would not produce an interface in Terra in which QuantumCircuit1 + QuantumCircuit2 equaled the Operator sum of the circuit unitaries, rather than simply appending the circuits. However, within the Operator flow summing the unitaries is the expected behavior.

Note that all mathematical methods are not in-place, meaning that they return a new object, but the underlying primitives are not copied.

Parameters

• primitive (Union[QuantumCircuit, Operator, Pauli, SparsePauliOp, OperatorBase]) – The operator primitive being wrapped.

• coeff (Union[complex, ParameterExpression]) – A coefficient multiplying the primitive.

Methods Defined Here

add	Return Operator addition of self and other, overloaded by +.
adjoint	Return a new Operator equal to the Operator’s adjoint (conjugate transpose), overloaded by ~.
assign_parameters	Binds scalar values to any Terra Parameters in the coefficients or primitives of the Operator, or substitutes one Parameter for another.
compose	Return Operator Composition between self and other (linear algebra-style: A@B(x) = A(B(x))), overloaded by @.
equals	Evaluate Equality between Operators, overloaded by ==.
eval	Evaluate the Operator’s underlying function, either on a binary string or another Operator.
exp_i	Return Operator exponentiation, equaling e^(-i * op)
log_i	Return a MatrixOp equivalent to log(H)/-i for this operator H.
mul	Returns the scalar multiplication of the Operator, overloaded by *, including support for Terra’s Parameters, which can be bound to values later (via bind_parameters).
permute	Permutes the qubits of the operator.
primitive_strings	Return a set of strings describing the primitives contained in the Operator.
reduce	Try collapsing the Operator structure, usually after some type of conversion, e.g.
tensor	Return tensor product between self and other, overloaded by ^.
tensorpower	Return tensor product with self multiple times, overloaded by ^.
to_circuit	Returns a QuantumCircuit equivalent to this Operator.
to_circuit_op	Returns a CircuitOp equivalent to this Operator.
to_instruction	Returns an Instruction equivalent to this Operator.
to_matrix	Return NumPy representation of the Operator.
to_matrix_op	Returns a MatrixOp equivalent to this Operator.
to_pauli_op	Returns a sum of PauliOp s equivalent to this Operator.

Attributes

INDENTATION = ' '

coeff

The scalar coefficient multiplying the Operator.

Return type

Union[complex, ParameterExpression]

Returns

The coefficient.

instance_id

Return the unique instance id.

Return type

int

num_qubits

Return type

int

parameters

primitive

The primitive defining the underlying function of the Operator.

Return type

Union[QuantumCircuit, Operator, Pauli, SparsePauliOp, OperatorBase]

Returns

The primitive object.

settings

Return operator settings.

Return type

Dict