SOFTWARE IMPLEMENTATION OF NUMERICAL ALGORITHMS OF SOLVING THE ELECTROMAGNETIC WAVE DIFFRACTION PROBLEMS BY PERIODICAL GRATINGS

Abstract

Some methods of program realization for algorithms of solving the infinite sets of linear algebraic equations arising in problems of electromagnetic wave diffraction by periodic gratings are presented. Diffraction problem solutions are considered in a class of quasi-periodic functions. Infinite sets of the equations are obtained by integral-summatory identity method from conjugation conditions of electromagnetic fields in the grating plane. The following questions are discussed: how to check operability of an algorithm quickly; how to make sure that results of the program work are reliable; how to optimize a program code and to reduce performance time? At the first programming stage it is recommended to use special classes for storage of elements of vectors and matrices. Methods of object programming allow to develope the general approach to program realization for solving algorithms of the two-dimensional and three-dimensional diffraction problems. It is expedient to store auxiliary arrays in memory that demands bigger random access memory of the computer, but reduces the execution time of the program. For the considered class of computing problems it is effectively to use technologies of parallel programming in calculating coefficients of the linear equations. The share of a parallel code in the program reaches 90-95%. Special attention is paid to questions of computer program testing. The limit special cases of the main problem, significantly simplifying calculations, are marked out for this purpose