Calculators

Calculators are essential in out modern life. Without a calculator we can not live. You do not agree?

• Your house and mortgage are based on financial calculations.
• Your SuperMarket heavily depends on the right calculation of your bill.
• Your Car makes an estimate when you need to refill.

Introduction

Calculators are available in different settings and methodology. Examples:

• Operating Systems
  • iOS, Apple mobile platform for iPad and iPhone
  • OSX, Apple desktop and Laptop platform for iMac and MacBook (pro).
  • Android, Google Mobile Platform
  • UNIX
  • Windows
• Methodology
  • Normal
  • Reverse Polish Notation (RPN)
  • Reverse Polish Lisp (RPL)
• Distribution
  • Local installed
  • Website

RPN & RPL

There exists mainly two kinds of reverse polish styles, RPN and RPL.

• RPN, the number you enter goes into the bottom of the stack (x-register for HP calculators).
  The "ENTER" key copies the contents of the x-register into the next y-register.
  • HP calculators like HP35, HP25, HP15, HP32S, HP42S, etc. fall into this category.
• RPL, the number you enter goes into an input buffer first.
  The "ENTER" key copies the contents of the input buffer into x-register.
  You can also enter a number followed by an operator. For example, 2+ adds 2 to x-register. 2 sin pushes sin(2) in x-register.
  • HP48 falls into this category.

If you are familiar with old HP calculators using RPN, you might get confused a little with RPL. For example, to calculate 2 + sin(2),

• in RPN, you do 2 ENTER sin + because you will have '2' in both x and y registers after hitting ENTER.
• In RPL, this is not the case, so you have to do 2 ENTER ENTER sin +.

For more details, take a look at Museum of HP calculators.

Financial Calculators

See:

• Finance Harm Frielink FinCalc, My own Financial Calculator
• Harm Frielink Financial Interest Calculator, Description of the Financial Calculator

PCalc

Probably the best calculator to get for OSX/iOS. But you have to pay for the OSX version. There is no one-pay install-anywhere. The initial iOS version is ok, you do not need the paid extensions. The calculator has RPN modus making it very fine to use.

Description	Pro's	Con's
Operating System	iOS OSX	Android Windows
Methodology	Basic RPN
Distribution	Local on OSX (iMac) Local on iOS (Apple App) Website all version (Internet)	Local on Android Local on Windows

HP Calc Emulators

It seems the HP-Calculators like me are getting old. If you are a (former) HP-Calculator freak (like me) look at the Website http://www.hpcalc.org/hp48/pc/emulators .

If you are looking to HP-Calculator for OSX look at the Japanese Website http://osksn2.hep.sci.osaka-u.ac.jp/~taku/osx/rpnosx.html

See also

• LinuxFocus.org, Guido's RPN calculators, RPN calculators are not so common because it takes a bit of learning until you can use them. However once you have understood the logic and used them for a while you would never want a different calculator again.