Sinclair ZX80 / ZX81 / Z88 Forums

I was inattentive, in EightyOne emulator ROM may be selected and with zx81.edition1.rom errors present.

Yes, my test code implicitly assumes double precision arithmetic (REAL*8), but ZX81 arithmetic is REAL*5 (32-bit for mantissa). So error 1E-16 unnecessary small. With 1E-8 as error limit result much more correct, but it differ from built-in sin 2.0980103 vs 1.9998355 (built-n sin) Maybe I would assu...

Some time ago, I decided to understand the floating point arithmetic and wrote a simple test that calculates the area under half the period of the sine function. It's not complete, but some results can be seen here http://avhohlov.narod.ru/p9882en.htm . Test may be done also on old home computers an...