The computer 500 shown in FIG. 16 comprises a CPU (Central Processing Unit) 510 that executes the program, an input device 520 such as a keyboard and a mouse, a ROM (Read Only Memory) 530 for storing various data, a RAM (Random Access Memory) 540 for storing calculation parameters and the like, a reader 550 that reads the program from the recording medium 600, an output device 560 such as a displa