WP 43S

[Claudio L.]

(05-01-2019 04:33 PM)Thomas Okken Wrote:  Mathematically speaking, a numerical multiple-input single-output solver, like the ones in the HP-42S and the RPL calculators, is no different than a single-input solver. It just provides a nice user interface for setting the constants and choosing which variable to solve for.

A true multi-variate solver, that finds a zero or extremum in a multi-dimensional search space, would be an entirely different challenge.

Well, newRPL has an implementation of the minimization algorithm by Nelder-Mead for the multiple solver, so it does indeed solve them all at once in multidimensional space. It wasn't as hard to implement as it may seem at first look, so I would encourage him to give it a shot (that one or any other algorithm, I agree with him that the multiple solver is a killer feature on any calc).