OK, I got your attention!

The 15c is a wonderful machine.

But:

after using a 32s, do you really think it makes sense to have keycodes instead of actual function names?

after using a 32sii, where you can enter many algebraic expressions into the solver, do you really want to have to program, in RPN, line by line, for every function solve or integrate problem?

after trying an editable Formula or true algebraic machine, such as a sharp pc 1500, (or even a Casio fx 115ms plus, or even HP30s), do you really really see an advantage to having a limited stack, intermediate operation machine, with no ablility to recall and edit and re-use an equation or expression, without turning it inside out in RPN? (The 17bii gives you the same feeling only better---editable, long variables, fully algebraic solver, returns the values to the stack...)

Afer the 33s, with its 32 kb (8 kb really when efficiency isconsidered) do you really think there is a reason to spend real money on a scientific calculator with less than 500 bytes?

After RPL, where you can evaluate an algebraic, DUP it, operate on it with stack logic, save it, edit it, merge it with other algebraics, re-use it, etc, is there really any reason for RPN?

Afer you have tried all of these machines, seen what is possible, enjoyed the absolutely beautiful design of the 15c, savored its remarkable power, acclimated to and internalized its keycodes......

Now, think logically, clearly, and efficiently for the future....why would you spend real money on a new device (without true collector value both nostalgic and monetary) with the limitations of the 15c?

The future is not RPN. But a stack could (and should even) be a part of the future. Algebraic objects should be normal standard fare---and they should be editable. Memory should be plentiful. Variables and registers, too.

I really like the 15c. I enjoy it. I use it regularly. I greatly appreciate Valentin's challenges, Karl's tips---- because I have one, and know it, I will use it. I like the user mode---I put what I use frequently under labels a through E and have direct access--its great!

But I can see that it is antiquated--a bit obtuse if you don't already know it......there is no reason to really produce it anymore in real nuimbers....you can do so much better!

Why should a person learn math, and then have to go learn a new way of writing math? Why shouldn't the rules of precedence, the notation, etc be the same as it is for maths? Why should a user have to be molded by the arbitrary limits of the machine's architecture, when it is perfectly possible with available technology, to develop an interface which is consistent with mathematical notation?

(I will note that most "algebraic" half-breeds (not good formula machines) are even worse when it comes to distortion--and the "4 function" types are abominable--as are old Ti's where clearing or overtyping after an incoorect operator will give unexpected results....at least RPN is consistent.)

Rather than bringing back the 15c, I think we should push, through openRPN, to develop a truly powerful machine, which is capable of working in the new paradigm.

Best regards,

Bill