Logic, logic, logic!!!

[Stefan]

(02-22-2014 09:29 PM)Matt Agajanian Wrote:  Hello all.

What makes TI's, HP's and Casio's direct formula/textbook entry methods different from each other?

My only TI is the NSpire CAS so this is not really comparable to the cheap calculators, but for the cheap scientific calculators my answer is this:

Casio fx-991ES Plus and fx-991DE plus:
sin, cos, tan and so on add a "(" to the function. this is often nice. but it also means you always have to type a closing ")"
The textbook entry gets very slow for large(and not so large) expressions. (See the other thread "calculator keys are made of plastic for more discussion). This is super annoying (and dangerous in exams).
Constants are written with the symbols (so instead of printing the value of epsilon_0 an the greek letter is printed. But therefore you have to look up the ID of the constant on the protective sleeve of the calc.
Textbook entry does also work in Complex mode.
The Casios loose all the history when you switch them off. Only variables (A, B, C... X, Y) are retained.
To switch display beteen proper fraction, non proper fraction and decimal fraction two different key presses are used.

Sharp EL-W506:
sin, cos, and so on don't include a "(". This is also kind of nice in cases where you dont need "()".
constants are printed as their value. But therefore the "constant" menu shows the name of the constant together with its unit. so you dont need to look it up anywhere.
The Textbook mode only works in the "normal" mode. does not work in "complex" mode.
The Sharp remembers everything even after switching it off.
To switch between fraction modes only one and the same key is used (all modes are cycled through after another)

Does that answer some of the questions?

My favourite is the Sharp EL-W506 (*not* EL-506W). But the HP300s+ seems also promising (see the other thread mentioned at the beginning)