>> Anyone know where I can find some 'C' source for a sine function that 
>> uses a
>> larger lookup table for more accurate results?  I am using the CCS C
>> compiler, and the results get pretty inaccurate when dealing with very 
>> small
>> numbers.

For small angles sin(x) = x (angle in radians) to a reasonably good 
approximation.
This is both easy and fast :-)

(This is obvious enough when you look at how sin is defined using a triangle 
but far from intuitive otherwise. The error relates to using a straight line 
to approximate the length of the circumferential arc subtended by the given 
angle on a unit radius circle. As the angle approaches zero the straight 
line and arc approach equality.). Whether this is good enough depends on 
your requirements.

Using degrees, error is 0.01% at 1 degree, 0.13% at 5 degrees, 0.51% at 10 
degrees, 2.1% at 20 degrees



        RM


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