QCircuit
Aids design of quantum circuits
QCircuit is an aid for understanding, designing, and simulating quantum circuits. You essentially drag-and-drop gates into place on a set of "wires" and see its effects. Currently implements the Hadamard and Not/CNot/Toffoli/etc. gates, as well as allowing you to define a gate with an arbitrary (2^n)x(2^n) complex matrix. You can feed input bits in one end of a circuit and watch the values change as they continue through the circuit, as well as retrieving the actual quantum state at any given point. I still have a number of features I want to implement, so I will likely be updating this in the future.
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