Re: How to use floating point in a module?

[Ian Kent]

On Sun, 30 May 2004 ndiamond@xxxxxxxxxxxxx wrote:

> 
> Yes, if we use a real-time Linux and make a daemon cooperate very closely
> with the driver.
> 
> >Maybe you could use lookup tables instead of doing floating point
> >arithmetic.
> 
> You might be right, if the device can only be controlled to position itself
> in say 1,000 different ways, then we could have lookup tables for 1,000
> different intervals of (emulations of) floating-point numbers, that yield
> 1,000 different values of sin.  Another table for cos, another for log10,
> etc.  But I'd still have to write my own emulations for binary operators
> such as +, /, etc., since a 1,000*1,000 lookup table would be too big.

Why not scaled longs (or bigger), scalled to number of significant 
digits. The Taylor series for the trig functions might be a painfull.

Ian

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