[Authors] Osipenko, G.S.; Romanovskii, I.V.; Ampilova, N.B.; Petrenko, E.I. [Title] On Morse spectrum calculation [AMS Subj-class] Primary: 37D45, Secondary: 37F15, 37M05 [Keywords] Morse spectrum, Lyapunov exponent, symbolic image, simplex-method, homoclinic point, hyperbolicity. [Abstract] Morse spectrum of a dynamical system is a limit set of Lyapunov exponents of periodic pseudo-trajectories. A constructive method, based on symbolic image conception, is considered to localize the Morse spectrum. The symbolic image of a dynamical system is a finite discrete approximation and constitutes a directed graph. The localizing method is based on a construction of special sequence of symbolic images and a search of closed paths having the wanted characteristics. The main difficulty is that the number of such paths dramatically increases. A new simplex-method based algorithm is considered. It has been implemented and the numerical results have been obtained for well-known systems. [Contact e-mail] nataly@is1483.spb.edu