## Hewlett Packard's Cult Calculator Turns 30 318

Hugh Pickens writes

*"The Wall Street Journal reports that Hewlett Packard's HP-12C financial calculator has remained outwardly unchanged since its introduction in 1981. 'Once you learned it on the 12C, there was no need to change,' says David Carter, chief investment officer of New York wealth-management firm Lenox Advisors, who has owned his 12C for 22 years and still keeps it on his desk. 'It's not like the math was changing.' The 12C, which costs $70 on HP's website, is HP's best-selling calculator of all time, though the company won't reveal how many units it has sold over the years. The 12C still uses an unconventional mathematical notation called 'Reverse Polish Notation,' which eschews parentheses and equal signs in an effort to run long calculations more efficiently."*
## you would think (Score:5, Informative)

You would think given that calculators still sell pretty well and this one is doing good for 30 full years that HP would maybe consider that they made a mistake in essentially killing off this line. Wouldn't it be wonderful it HP put out hand device for engineers as far advanced a the HPs were then?

Anyway the scientific version of the 12c is the 15c: http://www.hpmuseum.org/hp15.htm [hpmuseum.org]

And my love was the 28S. http://www.hpmuseum.org/hp28c.htm [hpmuseum.org]

## Re:Unconventional? (Score:2, Informative)

I thought those RPN folks were crazy until I had to write my own stack-based RPN calculator for a school assignment. There is nothing more awesome than being able to compute a quadratic formula without using grouping symbols.

## Re:Long Live the HP-48 (Score:4, Informative)

## Re:Unconventional? (Score:3, Informative)

## The "C" suffix and programming memories (Score:4, Informative)

The "C" suffix stood for "continuous memory", meaning that programs and data did not disappear when the calculator was shut off. Like what every calculator does today. Before then, however ...

My first HP was the HP-25, a glorious invention when it came out in 1975. It had 49 programming steps, and the program had to be re-entered from the keyboard, line-by-line, every time the calculator was turned off. My first real programming success came when a high school math teacher, trying to show how hard it was to determine whether a given number was prime or composite, asked my class to determine whether the number 300,000,007 was prime or not. (Thirty-five years later, I have not forgotten that number, and don't think I ever will.)

I was able to program a test for primality into the HP-25. It was brute-force, of course -- checked for an integer result when the argument was divided by two, and then every odd number from three up to the square root of the argument -- but it worked, and I was able to show that 300,000,007 was prime. The teacher was impressed, both with the calculator and with the fact that such a large number that she picked out of the air at random turned out to be prime. (I don't think she new or cared about programming.)

I love that calculator. The HP-25C came out the following year, and the HP-25 became an orphan, but I still have it -- along with an HP-48G+ purchased about 12 years ago. (Finding a new calculator with RPN turned out to be harder than I thought.)

## Re:Always have a phone, maybe not computer (Score:4, Informative)

As someone who posted up-thread about still using his 30 year old HP scientific calculator, and who

alsohas Mathematica installed on his small portable computer (a 13 inch TimelineX), I can address this. Each tool has its own area of ideal application. I can crunch through some rapid calculations with my little calculator much more easily than I can boot my laptop. load Mathematica, and enter the same series of numbers and operations in it, even if Ihavemy laptop with me. Pressing the sin button on my HP is faster than typing Sin[ ] on a keyboard.## There's a big problem with the "new" 12-C (Score:3, Informative)

## Re:Unconventional? (Score:4, Informative)

And in Unixland, an RPN calculator is often only as far away as a shell prompt: dc [unix.com]

Very handy.