SPSAEstimatorGradient¶

class SPSAEstimatorGradient(estimator, epsilon, batch_size=1, seed=None, options=None)[source]¶

Bases: BaseEstimatorGradient

Compute the gradients of the expectation value by the Simultaneous Perturbation Stochastic Approximation (SPSA) [1].

Reference: [1] J. C. Spall, Adaptive stochastic approximation by the simultaneous perturbation method in IEEE Transactions on Automatic Control, vol. 45, no. 10, pp. 1839-1853, Oct 2020, doi: 10.1109/TAC.2000.880982

প্যারামিটার

estimator (BaseEstimator) -- The estimator used to compute the gradients.
epsilon (float) -- The offset size for the SPSA gradients.
batch_size (int) -- The number of gradients to average.
seed (int | None) -- The seed for a random perturbation vector.
options (Options | None) -- Primitive backend runtime options used for circuit execution. The order of priority is: options in run method > gradient's default options > primitive's default setting. Higher priority setting overrides lower priority setting

রেইজেস

ValueError -- If epsilon is not positive.

Methods

`run`	Run the job of the estimator gradient on the given circuits.
`update_default_options`	Update the gradient's default options setting.

Attributes

derivative_type¶

Return the derivative type (real, imaginary or complex).

রিটার্নস: The derivative type.

options¶

Return the union of estimator options setting and gradient default options, where, if the same field is set in both, the gradient's default options override the primitive's default setting.

রিটার্নস: The gradient default + estimator options.