pygsti.algorithms.scoring.filter_composite_rcl

filter_composite_rcl(candidate_scores, alpha)

Create a restricted candidate list (RCL) based on CompositeScore objects.

Parameters:

• candidate_scores (list of CompositeScore) – List of scores to be sorted in RCL and not RCL.

• alpha (float) –

  A number between 0 and 1 that roughly specifies a score threshold relative to the spread of scores that a germ must score better than in order to be included in the RCL. A value of 0 for alpha corresponds to a purely greedy algorithm (only the best-scoring element is included in the RCL), while a value of 1 for alpha will include all elements in the RCL.

  Intermediate values of alpha attempt to mimic the behavior of alpha for simple float scores. For those scores, the score that all elements must beat is (1 - alpha)*best + alpha*worst. For CompositeScore objects, thresholding is done on the major part of the score unless all the candidates have the same major score, in which case thresholding is performed using only the minor score.

Returns:

The indices of the scores sufficiently good to be in the RCL.

Return type:

numpy.array