advantages of RPN

[Don Shepherd]

(05-22-2014 03:08 PM)Alvaro Wrote:  Let me say like this: There are much better options.

If the HP50g had a BASIC language on it I am sure it would be the "Ultra Calculator of the Century".

My personal opinion is that it will be very difficult to find something worst than UserRPN as a "programing Language".
While I agree that for manual calculations there is some advantage of PRN, I even like it, but as a "Programing Language" is the worst I can imagine.

UserRPL is very difficult to read, to follow.
UserRPN makes heavy usage of the stack. So, while READING or PROGRAMING you have to do a big effort to follow what is happening on the Stack what makes it much difficult to read, besides the huge usage of all sort Brackets.

Not forgetting the unpossibilty of programing on a Desktop PC, run it there and transfer the ready Programm to the HP

I disagree of the advantage people are saying about "user interact" with stack. For me that is something like "marketing".

Alvaro, programming languages exist to enable people to solve problems on computers. A programmable calculator is a computer. I probably wouldn't try to write a payroll program on a programmable calculator, but there are all kinds of problems that lend themselves to solution on a calculator, and an RPN calculator is a suitable device for such problems.

A forum user sent me a copy of the HP-65 User's Library Catalog, dated April, 1975, which is 15 months after the HP-65 was introduced. This catalog lists programs written by HP-65 users, to be shared with other users. In those 15 months, approximately 600 users submitted approximately 2,000 RPN programs. Those were useful programs for solving real problems. In 1975, NASA developed RPN programs for the HP-65 carried aboard the Apollo-Soyuz Test Project, which would have been used had the onboard Apollo Guidance Computer failed.

HP has not made an RPN calculator--other than the venerable 12c--in many years, but there are lots of people out there today, in 2014, using RPN calculators and writing useful routines for their application area. And there are many members of this forum doing the same. I have written probably a few dozen HP-65 programs to help me as a math teacher. Forty years later, it is still going strong!

Like I said, I wouldn't write a payroll program on my 65, but RPN programs are both valid and useful.