mthree.utils.expval_and_stddev

expval_and_stddev(items, exp_ops='')

Compute expectation values from distributions.

Added in version 0.16.0:

Parameters:

items (list or dict or Counts or ProbDistribution or QuasiDistribution): Input

distributions.

exp_ops (str or dict or list): String or dict representation of diagonal qubit

operators used in computing the expectation value.

Returns:

float : Expectation value. ndarray: Array of expectation values

Notes:

Cannot mix Counts and dicts with M3 Distributions in the same call.

The dict operator format is a sparse diagonal format using bitstrings as the keys.