The purpose of the present report is to describe in complete detail a FORTRAN codenamed Program SCAT 4 written by the UCLA group in order to analyze elastic scatteringof various particles against complex nuclei by means of the diffuse surface optical modelof the nucleus.While a number of similar programs have been prepared and used by other groups,there have been many requests for the UCLA program because of its flexibility and theavailability of IBM 704 and 709 computers for which the program i ...