Relative speed of 15C, 34S and 42S

[Dieter]

(12-25-2017 04:27 PM)Michael de Estrada Wrote:  I recently received a DM42, and was curious as to its relative speed when compared to the original HP model as well as other similar models. I used a program originally written for the HP-15C that makes use of matrix operations and the root solver.

This may be not the best idea for comparing speeds since the matrix and solver algorithms may be different. This is especially true for the 34s which definitely uses its own methods.

(12-25-2017 04:27 PM)Michael de Estrada Wrote:  The most surprising result to me is how much faster the DM 42 runs, despite using twice the precision of the other calculators

The 34s does its internal calculations with 39 (!) digits, XROM code with 34, and sometimes even more, so its working precision is at least on par with the DM42. This happens both in single and double precision mode.

(12-25-2017 04:27 PM)Michael de Estrada Wrote:  and not having the fastest CPU clock.

Is it true that the DM42 switches to a higher clock rate when connected to USB power? If yes, results for both rates may be interesting.

Dieter