pygsti.gram_rank_and_evals¶
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pygsti.
gram_rank_and_evals
(dataset, specs, targetGateset=None, spamDict=None)¶ Returns the rank and singular values of the Gram matrix for a dataset.
Parameters: - dataset (DataSet) – The data used to populate the Gram matrix
- specs (2-tuple) – A (prepSpecs,effectSpecs) tuple usually generated by calling build_spam_specs(...)
- targetGateset (GateSet, optional) – A gateset used to specify the SPAM labels used to connect the dataset values to rhoVec and EVec indices.
- spamDict (dictionary, optional) – Dictionary mapping (rhoVec_index,EVec_index) integer tuples to string spam labels. Defaults to the spam dictionary of targetGateset e.g. spamDict[(0,0)] == “plus”
Returns: - rank (int) – the rank of the Gram matrix
- svalues (numpy array) – the singular values of the Gram matrix
- svalues_target (numpy array) – the corresponding singular values of the Gram matrix generated by targetGateset. (or None if targetGateset is None)