Student Posters Repository

In solving complex symmetric linear systems arising from the edge finite element method with double precision number, we suffer from slow or no convergence of iterative methods. Here, in real number problems, high precision calculation improves the convergence of the iterative method. Therefore, we implement multiple-precision calculation, especially, double-double (DD) precision numbers, which is implemented with two double precision type variable.  As a result of numerical experiments, when solving the complex symmetric linear equation, we succeeded in improving the convergence of the iterative method by using high precision calculation, and by using mixed precision calculation with high precision calculation and double precision calculation, we succeeded in suppressing the increase of calculation time.Moreover, we succeeded in suppressing the influence of acceleration factor and relaxation coefficient in preconditioning matrix calculation by high precision calculation.Thereby, I succeeded in getting convergent solution stably. In future, we aim to realize more speedup by implementing parallelization, and utilizing high-performance computing technology using Intel AVX instruction and so on.