I found a very interesting article by a UC Berkeley math & engineering professor (W. Kahan) about calculation roundoff errors and poor processor architectures. What's interesting is that he compares HP with TI financial calcs, and he was actually involved in the coding of the *original* 12C's algorithms. I'm posting this as a follow-up on the controversy about the 12C Platinum's "solving for i". Dr. Kahan's article (pp. 14-19) discusses this issue quite in depth (for the original 12C). You can be quite sure the 12C Platinum does not use his beautiful ideas or it would be *at least* as fast as the 12C. I wouldn't be surprised if HP simply "lost" the original coding ideas used for the 12C and tried to reinvent the wheel (and if you read the article, you'll see reinventing *this* wheel isn't quite as simple as it initially appears). The article, called "Mathematics Written in Sand", is linked to from Dr. Kahan's web page at:

http://www.cs.berkeley.edu/~wkahan/

The direct URL is:

http://www.cs.berkeley.edu/~wkahan/MathSand.pdf

Eduardo