FrozenParameterGate

class FrozenParameterGate

Bases: ComposedGate, LocallyOptimizableUnitary, DifferentiableUnitary

A composed gate which fixes some parameters of another gate.

__init__(gate, frozen_params)

Create a gate which fixes some of the parameters it takes.

Parameters:

• gate (Gate) – The Gate to fix the parameters of.

• frozen_params (dict[int, float]) – A dictionary mapping parameters indices to the fixed value they should be.

Raises:

ValueError – If any of the frozen_params indices are greater than the number of parameters gate takes or less than 0 or if the total amount of frozen_params is larger than the number of parameters gate takes.

Attributes

dim	The matrix dimension for this unitary.
name	The name of this gate.
num_params	The number of real parameters this unitary-valued function takes.
num_qudits	The number of qudits this unitary can act on.
qasm_name	The qasm command for this gate, see Gate for more info.
radixes	The number of orthogonal states for each qudit.

Methods

check_env_matrix(env_matrix)	Check to ensure the env_matrix is validly shaped.
check_parameters(params)	Check parameters are valid and match the unitary.
get_full_params(params)	Returns the full parameter list for the underlying gate.
get_grad([params])	Return the gradient for this gate.
get_inverse()	Return the gate's inverse as a gate.
get_inverse_params([params])	Return the parameters that invert the gate.
get_qasm(params, location)	Returns the qasm string for this gate.
get_qasm_gate_def()	Returns a qasm def for this gate, see :class:Gate for more.
get_unitary([params])	Return the unitary for this gate, see Unitary for more.
get_unitary_and_grad([params])	Return the unitary and gradient for this gate.
is_constant()	Return true if this unitary doesn't take parameters.
is_differentiable()	Check if all sub gates are differentiable.
is_locally_optimizable()	Check if all sub gates are locally optimizable.
is_parameterized()	Return true if this unitary is parameterized.
is_qubit_only()	Return true if this unitary can only act on qubits.
is_qudit_only(radix)	Return true if this unitary can only act on radix-qudits.
is_qutrit_only()	Return true if this unitary can only act on qutrits.
is_self_inverse([params])	Checks whether the unitary is its own inverse.
optimize(env_matrix)	Return the optimal parameters with respect to an environment matrix.
with_all_frozen_params(params)	Freeze all of a gate's parameters so they don't change from optimization.
with_frozen_params(frozen_params)	Freeze some of a gate's parameters so they don't change from optimization.