>...

> Steve> There is a nice summary of common methods at

> Steve>

> http://www.interstice.com/~sdattalo/technical/theory/sinewave.html.

> This is a very nice URL. I might add that there is a good book

> called "Computer Approximations" that has several descriptions

> of series to approximate different functions. It includes a

> five term polynomial that is a chebysev fit to the function

> 'sin (pi/2* X)'...

I'd like to second his observation about this fine book. We have

used it since the '70s as the basis for fixed-point fraction

arithmetic libraries in our embedded systems products. You can

get excellent performance and accuracy this way without the overhead

of floating point on chips that don't have hardware FP.

The book is a little hard to find, though. A complete reference (from

the last one we bought, in 1983) is:

Computer Approximations, by John F. Hart et. al.

Robert E. Krieger Publishing Co.

Malabar, FL

ISBN 0-88275-642-7

Original ed. 1968, John Wiley & Sons, Inc.

Reprinted in 1978 w/ corrections by Krieger

Enjoy,

Elizabeth

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