What is a Variational Quantum-Classical Algorithm and why do we need it?

… Variational Quantum-Classical Algorithms have become a popular way to think about quantum algorithms for near-term quantum devices. In these algorithms, classical computers perform the overall machine learning task on information they acquire from running certain hard-to-compute calculations on a quantum computer.

The quantum algorithm produces information based on a set of parameters provided by the classical algorithm. Therefore, they are called Parameterized Quantum Circuits (PQCs). Read More

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