This report discusses the application of the following methods that are used to calculate maximum frequency of a spectrum: parabolic, modified parabolic by Rife and Vincent, powell and mahoney bloody mary mix the method according to Quinn from 1994 and the method according to Quinn from 1997.After introducing DIRECT global minimization method, the results obtained using previously mentioned methods are compared with the results obtained using DIRECT global minimization of the Lipschitz function.Determining vibration frequency and comparing to previously collected data or knowledge base data is a common procedure.In engineering practice iphone 14 price san francisco it is often necessary to determine not one, but several so-called dominant frequencies or local maxima; the procedure is sometimes called multi peak detection and here we propose an algorithm for computerised multi peak detection.