(12C) Trigonometric Functions

[Gerson W. Barbosa]

(07-01-2016 02:15 AM)rprosperi Wrote:  I believe the program has been posted before, but having this all in one place with all the background material included makes it a clear and handy resource.

I am glad you have appreciated it. Actually much background material is missing. Rather than plain Taylor series, this program is based on polynomial approximations on limited ranges, which are then expanded to the full working ranges by means of trigonometric identities. This is better explained in an old version of this program:

Fast and Accurate Trigonometric Functions on the HP-12C

The "fast" part is ok, but the "accurate" term has been somewhat innaccurately used there (even this later version, despite the higher-degree polynomials, doesn't offer always full accuracy).

An earlier version of the current program has been posted here. The whole thread is interesting taking a look at as more background information is available there, including some ideas and suggestions from Bob Shoring and Willy Kunz, the author of the RPN-38 CX Simulator, which made into this program and the one written specifically for the simulator.

Best regards,

Gerson.

Edited to fix a typo.