BASIC Programs on HP 50G

[Wes Loewer]

(03-26-2014 08:46 PM)Alvaro Wrote:  Programing in RPL has a very interesting particularity: Every time you make a user INPUT you have to declare another PROGRAM begin or you have to SAVE that input variable a as GLOBAL so that a the end you have all your HP50g FULL of USELESS variables that you will need to PURGE manually. Weird, I would say.

I think you missed the point of RPL being a stack based language. While you could use local or even global variables, a common method is to just use the stack. Perhaps an example would help. Here's the same Hi-Lo demo program again in RPN mode using no local or global variables.

Code:

\<< RAND 100. * 1. + IP "GUESS A NUMBER, 1-100" "" INPUT OBJ\->
  DO
    IF DUP2 <
    THEN DROP "TOO HIGH" "" INPUT OBJ\->
    ELSE
      IF DUP2 >
      THEN DROP "TOO LOW" "" INPUT OBJ\->
      END
    END
  UNTIL DUP2 ==
  END
  CLLCD " IS CORRECT!" + MSGBOX DROP
\>>

-Wes L