At 11:41 AM 4/6/00 -0700, you wrote:
>I am looking for a PIC (16F84 or similar) assembler routine to compute
>arcsin with 32 bit floating point numbers.  Routines using lookup
>tables and interpolation need not apply, this needs to be accurate.
>Alternately, a good arctan routine would be acceptable, but I do need
>arcsin for this application and so I would have to compute an extra
>square root, which I'd like to avoid.  I thought I found an arctan
>routine on the web, but now I can't locate the link.

CORDIC algorithms (do a web search) would probably be the best choice
if you really need ~32 significant bits of result.

If you have any application where the numbers have *physical* meaning,
it's unlikely you'd need more than a 16 segment/16 bit table that
might yield 12 or 13 bits of accuracy.(~0.02%). IMHO, of course.

Best regards,
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