itsubaki/q

How do you specify control and target qubit for CNOT?

Closed this issue · 4 comments

divan commented

Hey, I'm a bit confused by CNOT API. in Microsoft Q# API of CNOT is really simple - you specify control and target qubits. How it can be implemented with this library?

itsubaki commented

Hi, You can use gate.ControlledNot(numberOfQubit, control, target int) instead of gate.CNOT().

divan commented

@itsubaki ah, thanks, missed it. Sorry for the lame question, but why control and target are ints? If I have c and t qubits, how to I apply ControlledNot on them?

itsubaki commented

ok. qubits is vector, gate is matrix in this library. control and target is index of qubits. this library can not be considered separately qubits. because qubits is possible to take the quantum entanglement state. and I don't know implementation for quantum entanglement operation in Q#. I will check Q# later.

example

c := qubit.One()
t := qubit.Zero()
q := qubit.TensorProduct(c, t)
// q -> |1>|0>
// it means  q[0] -> |1>, q[1] -> |0>

cnot := gate.ControlledNot(2, 0, 1)
q.Apply(cnot)
// q -> |1>|1>
divan commented

@itsubaki awesome, thank you!

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