A graphical method of evaluating the describing function

The describing function for a nonlinear element is evaluated from the nonlinear characteristic without going to the output waveform, and is shown to be a fraction of a certain area obtained by a simple graphical construction. The method is applicable to all nonlinearities. Phase shift, if any, is also determined in terms of areas. A template is suggested to speed up the graphical procedure. Simple as it is, the method presented is believed to be novel.