Wag the dog- Harmonic Oscillator
This method shows numerically, how the Schrodinger equation for a particle in a potential well V(x) has physical solutions only for certain values of energy. The standard analytical treatment of this problem involves using a series solution, where it is shown that the series converges only for certain values of energy (Refer Griffiths, Quantum Mechanics). Here a numerical method is used, and a slider for energy is used to show that the solution looks admissible only at certain energy values.