We are given a noisy observation x0 = h ∗ x + noise. We want to recover the true sharp image x by solving the Tikhonov-regularized least-squares problem minx ‖ h ∗ x − x0 ‖22 + λ ‖ x ‖22. "Run" solves it using the either closed-form (exact) or gradient descent (iterative).