reduce_merge_histograms¶

reduce_merge_histograms(grouped)[source]¶

Reduce grouped probability dicts by averaging across groups.

For PROBS / COUNTS results only. Equivalent to the VQA _average_probabilities logic: for each base_key, collects all probability dicts, unions all bitstrings, and averages the probability values. Used by TrotterSpecStage in measurement pipelines to merge probability histograms across Hamiltonian samples. For EXPVALS results (floats or per-observable lists) use reduce_mean() instead.

Raises:: TypeError – If a grouped value is not a dict (an EXPVALS float or list), naming reduce_mean() as the fix.

Example:

>>> grouped = {(('circ', 0),): [{'00': 0.6, '11': 0.4}, {'00': 0.8, '11': 0.2}]}
>>> reduce_merge_histograms(grouped)
{(('circ', 0),): {'00': 0.7, '11': 0.3}}

Return type:: dict[Any, Any]