Quantum ToolkitTypesStateMethodsnormOn this pagenorm Method of State. norm() -> real Computes the norm of the quantum state. Returns the squared L2 norm ∣∣ψ∣∣=⟨ψ∣ψ⟩\vert \vert \psi \vert \vert = \sqrt{\langle \psi \vert \psi \rangle } ∣∣ψ∣∣=⟨ψ∣ψ⟩ of the quantum state.