HP35s Revisited Trig Quandary Bug # 2

[Manolo Sobrino]

No series in there Marcus, but precomputed tables and CORDIC.

I don't think (now) that the 35s has a real trig bug, but some idiosyncrasies and not an entirely consistent behaviour. In fact, after having a look at it again, I'm reconsidering the 35s. Maybe I'll get one after all.

I've checked the tables from Karl Schneider (message #27) in:

http://www.hpmuseum.org/cgi-sys/cgiwrap/...ead=123814


The "dud" results resemble what I'd expect from a single precision calculation, that is, for an x precision calculator you can't have x significant figures in every trig function value because that would mean that you can work to double precision, but except for these special cases you can't, so these figures are basically pointless (and might lead you to "wrong" results, check thread below). It would be even better if for values closer to pi/2 in the cosine of (pi/2-x) this calculator would keep the consistent policy instead of returning the "perfect" 12 digit results everywhere that many HP fans are so fond of (but I must confess make me cringe).

(More on this: http://www.hpmuseum.org/forum/thread-1033.html)