> I know a lot can be optimized, but unfortunately it's not one of my
> strong points. :) I tried to rewrite the formula, but none of the other
> forms gave me anything that was more efficient computationally.
>
> The formula calculates acceleration, measured by a digital
> accelerometer. The T1's en T2's are intervals whose variation is a
> measure of acceleration, relative to calibrated measurements as T1Cal
> (ZCal) and T2Cal. So a division like T2/T2Cal will always be close to 1.
> The output y is a measure for the acceleration. This will later be used
> in arcsin, sin and cos calculations. The result of those are arctan'ed;
> that's why I need precision.
>
> The range of the variables is about 0-20000, so their product is 4x10^8
> worst case. which is pretty much 32bit for my taste (ok it's 29, or 30
> with sign; close 'nuff :)).
>
> Anyway, y is always between -2 and +2. I do believe I need floats, but I
> may be mistaken.

        You don't need floats at all. Floats only give you wide ranges, not
precision. Fixed point will easily due in your case. TTYL

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