######################## Your first calculation ######################## The shortest path from a fresh installation to a number. A single water molecule, one input file, one ``koopmans run``, and the energies of its highest occupied and lowest unoccupied orbital read off the output. Nothing here needs any prior knowledge of Koopmans functionals; the tutorials that follow explain what the calculation was actually doing. .. note:: This tutorial has not been written yet. It is tracked by `issue #62 `_.