Articles or book(s) about the functions behind a scientific calculator

[Thomas Klemm]

(11-25-2018 06:11 AM)Dan Wrote:  Also looking to write an editor for entering equations for the solver and for graph sketching, e.g. typing x^2 + 1 results in ENTER 2 ^ 1 + .

On the HP-48 you can install examples by executing the TEACH command.
They are installed in a new directory EXAMPLES.
Further down in PRGS is a program →RPN that allows to translate algebraic expressions to RPN.

Example:

'X^2+1'
→RPN
{ X 2 ^ 1 + }


And then there's the AECROM module for the HP-41 that allows to generate program code based on an equation:

Example:

PROG EXAMPLE
ENTER:FORMULA
X↑2+1
R/S
ENTER:LBL,CONS
X . .=
R/S
ANS=
R/S
PROGRAMMING. .
PACKING
RUN SIZE>=01


This results in the following program:

Code:

LBL "EXAMPLE"
"X=?"
PROMPT
STO 00
2
Y↑X
1
+

How cool is that?

Cheers
Thomas