Development and acceleration of multiple precision arithmetic toolbox MuPAT for Scilab

抄録

MuPAT enables the users to easily treat quadruple and octuple precision arithmetics as well as double precision arithmetic on Scilab. Using external C routines, we have also developed a high speed implementation MuPAT_c for Windows, Mac OS, and Linux. MuPAT_c reduced the computation time especially for all octuple precision arithmetic and inner product of quadruple precision arithmetic. MuPAT_c can run 90-1200 times faster than MuPAT. We applied three different precisions to tridiagonalization by the Lanczos method and confirmed that a high precision arithmetic was essential for the Lanczos method to get accurate eigenvalues of real symmetric matrices.