Consumer Reports likes Numworks

[John Keith]

(10-23-2021 08:02 AM)Wes Loewer Wrote:  I guess I fall in the other camp. I've often lamented the fact that the symbols for subtraction and negation look so similar. I wish they looked completely different from each other so that students would not confuse the two operations.



With most calculators, pressing a binary operator first, like +-*/^, generates Ans+, Ans-, Ans*, etc. With the NumWorks not having a separate negative key, all the operators work in the same manner except for subtraction. NumWorks assumes you are entering a negative number, which is logical if you don't have a separate negative key. Of course, you can manually enter ans-, but I prefer consistency. (I really hated how list processing on the 50g worked for all the math operators except +.)

HP calculators use either CHS or +/- for negation and - for subtraction, which is non-ambiguous, but also necessary for RPN since subtraction is a 2-argument function and negation is a 1-argument function. Having two different keys on an algebraic calculator is not necessary since the - in [b-]4-2[/b] is the same symbol as in -5. The Ans operation in modern calculators is a valid reason for two separate keys but they should be easy to distinguish as they are on HP calculators.

The inconsistency regarding + vs ADD for lists is an unfortunate legacy of using + to concatenate lists on the earlier RPL calculators. When listability of functions was implemented in the 48G, they had to use a different function name or else break compatibility with earlier models. NewRPL attempts to correct the situation by switching the meanings of + and ADD but I personally find ADD to be less than intuitive for list concatenation.