Dave-

I wanted to perform trig functions on integers in the range of +/-
1,000,000. I figured I would represent these numbers with three
bytes. But what I really want is to plot circles, and I'm now
thinking that x^2 + y^2 = r^2 will be much faster. I'd like to get
each answer in less than 100 microseconds, and the CCS C compiler is
much too slow.

I'm on the trail of square root functions in the piclist archives,
but they use non-standard mnemonics and my initial conversions don't
give me correct answers.

Seems like there's always one more obstacle....


At 8:31 AM -0800 11-21-03, David Minkler wrote:
>I'm confused.  The functions sin and cos evaluate to values in the range
>-1 to 1.  What do you mean by three-byte INTEGERS?  Do you really just
>want the sign of the function?
>
>Assuming that what you really want is a floating or fixed point real,
>how much precision does the CCS C compiler give you?  How many bits of
>accuracy do you need?  How fast do you need it to be?

--

Bryan Mumford
Santa Barbara, California
http://www.bmumford.com

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