Shades of purple and black/learning the HP-12c.

The base of my left ankle has turned a nice shade of purple and black. The swelling has gone down and the pain has subsided. Although there's plenty of stiffness and immobility to get through. I've been staying off of it as much as possible and pretty much am just sitting around reading.

I got an introduction to basic accounting methods from my dad the other night as we discussed double-entry book keeping, credit/debit "T" accounts. On top of that I'm getting the hang of using the Hewlett Packard 12C financial calculator which I bought at the college store in Geneva during sophomore year. It's amazing! I've been playing with calculating time value of money (how much is your money worth to you today vs. next year given a predetermined interest rate.) I understand better now the sub prime crisis and how speculation in real estate prices led to the disaster.

It just blows me away the functions of this tiny little calculator that uses Reverse Polish Notation; which is a big time saver over algebraic. Add to the fact that the design is over 25 years old and you can throw it against a wall and it will still work fine.

Reverse Polish Notation:

Your typical calculator like the Ti-83 uses the standard algebraic notation of 1+1=. If you key that in, it takes 4 strokes to get to the answer. And subsequent arithmetic on top of that requires at least 3 additional keystrokes. Your answer is 2 and you want to add 2 to that which is +2=. In RPN (reverse Polish) it's a bit different. 1 'Enter' 1+ gets the answer 2, still 4 strokes. However, additional arithmetics need only require the number and then the desired operation. So the solution was 2 and we're going to add 2 to it just like before. In RPN it is: 2+. That's it, just 2 additional keystrokes (more if you have more digits but always one less than standard algebraic.)

The other nice feature about the HP 12C is few people know how to use them and therefore it's is safe from being 'borrowed' off your desk by co-workers. Dr. Halfman who was my advisor at HWS always left one on his desk with is assortment of other calculators. The 12C never got swiped by students or faculty when his door was open. Add to the cushy corporate styling of the extruded aluminum cover and gold plated LCD and snappy plastic leather belt holster with magnetic closure.