qat.pylinalg.simulator.measure

qat.pylinalg.simulator.measure(state_vec, qubits, nb_samples=1)

Samples measurement results on the specified qubits.

No projection is carried out ! See “project” function. Thanks to the absence of projection, several samples can be asked.

Parameters

• state_vec (numpy.ndarray) – the numpy.ndarray containing full state vector.

• qubits (list) – list of integers specifying the subset of qubits to measure.

• nb_samples (int, optional) – the number of samples to return. Set to 1 by default.

Returns

intprob_list, a list (of length nb_samples) containing tuples of the form (integer, probability). The integer is the result of the measurement on the subset of qubits (when converted to binary representation, it needs to have a width of len(qubits)). The probability is the probability the measurement had to occur. It is useful for renormalizing afterwards. In short: it is a list of samples. One sample is a (int, prob) tuple.

Return type

list