In qiskit,i use
get_statevector method to get the statevector from my circuit.
What i want to know is how many times the circuit need to run.
Does is it only one?
It depends on whether you are simulating an ideal circuit or a noisy circuit. For ideal circuits, the number of
shots shouldn't have any effect on the result.
On the other hand, the number of
shots affects the result of simulating noisy circuits. According to the official documentation:
For noisy simulations each shot samples a randomly sampled noisy circuit from the noise model.