pygsti.modelmembers.operations.staticunitaryop
¶
The StaticPureOp class and supporting functionality.
Module Contents¶
Classes¶
A unitary operation matrix that is completely fixed, or "static" (i.e. that posesses no parameters). |
- class pygsti.modelmembers.operations.staticunitaryop.StaticUnitaryOp(m, basis='pp', evotype='default', state_space=None)¶
Bases:
pygsti.modelmembers.operations.denseop.DenseUnitaryOperator
,pygsti.modelmembers.errorgencontainer.NoErrorGeneratorInterface
A unitary operation matrix that is completely fixed, or “static” (i.e. that posesses no parameters).
- Parameters
m (array_like or LinearOperator) – a square 2D array-like or LinearOperator object representing the operation action. The shape of m sets the dimension of the operation.
basis (Basis or {'pp','gm','std'}, optional) – The basis used to construct the Hilbert-Schmidt space representation of this state as a super-operator.
evotype (Evotype or str, optional) – The evolution type. The special value “default” is equivalent to specifying the value of pygsti.evotypes.Evotype.default_evotype.
state_space (StateSpace, optional) – The state space for this operation. If None a default state space with the appropriate number of qubits is used.
- taylor_order_terms(self, order, max_polynomial_vars=100, return_coeff_polys=False)¶
Get the order-th order Taylor-expansion terms of this operation.
This function either constructs or returns a cached list of the terms at the given order. Each term is “rank-1”, meaning that its action on a density matrix rho can be written:
rho -> A rho B
The coefficients of these terms are typically polynomials of the operation’s parameters, where the polynomial’s variable indices index the global parameters of the operation’s parent (usually a
Model
), not the operation’s local parameter array (i.e. that returned from to_vector).- Parameters
order (int) – Which order terms (in a Taylor expansion of this
LindbladOp
) to retrieve.max_polynomial_vars (int, optional) – maximum number of variables the created polynomials can have.
return_coeff_polys (bool) – Whether a parallel list of locally-indexed (using variable indices corresponding to this object’s parameters rather than its parent’s) polynomial coefficients should be returned as well.
- Returns
terms (list) – A list of
RankOneTerm
objects.coefficients (list) – Only present when return_coeff_polys == True. A list of compact polynomial objects, meaning that each element is a (vtape,ctape) 2-tuple formed by concatenating together the output of :method:`Polynomial.compact`.
- property total_term_magnitude(self)¶
Get the total (sum) of the magnitudes of all this operator’s terms.
The magnitude of a term is the absolute value of its coefficient, so this function returns the number you’d get from summing up the absolute-coefficients of all the Taylor terms (at all orders!) you get from expanding this operator in a Taylor series.
- Returns
float
- property total_term_magnitude_deriv(self)¶
The derivative of the sum of all this operator’s terms.
Computes the derivative of the total (sum) of the magnitudes of all this operator’s terms with respect to the operators (local) parameters.
- Returns
numpy array – An array of length self.num_params
- _is_similar(self, other, rtol, atol)¶
Returns True if other model member (which it guaranteed to be the same type as self) has the same local structure, i.e., not considering parameter values or submembers