Re: Taylor series FSIN, FCOS, FTAN

On Apr 27, 12:30 pm, Albert van der Horst <alb...@[EMAIL PROTECTED]
>
wrote:
> For large values you should do range reduction. It amount to
> subtraction multiples of 2*pi and such. At least try to land
> in the [-PI, PI] interval.
> It is wise to at least take that from the sources I supplied. This
> greatly affects precision. If you omit range reduction, with your
> Taylor series, it still works in principle.
> For Chebychev it breaks down.

: REDUCE.2PI                   \ x
        PI*2                    \ x pi2
        FOVER FOVER F/          \ x pi2 x/pi2
        FLOOR                   \ x pi2 i(x/pi2)
        FOVER F*                \ x pi2 mod(x,pi2)
        FROT                    \ PI2 MOD(X,PI2) X
        FSWAP F-                \ PI2 MOD(X,PI2)
        FOVER 2E F/ FOVER       \ PI2 MOD PI MOD
        F< IF FSWAP F- ELSE FNIP THEN ;

I took this one from your source, but I'm unable to figure out what
you're trying to do at:

        FOVER 2E F/ FOVER       \ PI2 MOD PI MOD

Where does "2E" come from all of a sudden? And why isn't it converted
to a float before using it?

Hans Bezemer