RPN or Reverse Polish Notation

Most frequently, calculators are designed to identify simple operations like they are written. However, RPN or Reverse Polish Notation is a faster system of inputting information and equations. It will also help when performing complicated operations with your calculator.

Anyone utilising a calculator can learn to use Reverse Polish Notation calculators. Learning the simple concepts will be done within thirty minutes; however, mastering it can only come after practising. Hewlett Packard has manufactured Reverse Polish Notation calculators in the past, and one of the most popular ones is the HP 48G. There are Reverse Polish Notation calculators available on the Internet as well.

It is also advisable to remember that the most common way of inputting data into a regular calculator is usually in the same order as it is spoken or written. In contrast, an RPN calculator does not do it in this exact order. For instance, to perform the operation 9+6 on an RPN-based calculator, we will press 9, then ENTER, then 6, then +. With a regular calculator, we would press 9, then +, then 6, then ENTER or equal sign.


First step: stack

Firstly, we need to learn about the stack. Reverse Polish Notation calculators have several rows. The stack is the actual collection of the rows. Numbers are placed in the stack's initial row (bottom row), and the numbers right above it will move to the next row. However, only several rows are seen, and rows will be created for each new data set that isn’t displayed at that moment. We need to press the number and ENTER to put numbers on the stack. To copy the entire row, we must press ENTER, and the initial row will be copied to the second row. That’s precisely how the data is entered into the calculator.

Second step: deleting the data

There are several ways to eliminate the data from the stack. To clear the bottom row, the button shaped like an arrow pointing left will remove it. To remove the whole stack, press the DEL button (delete).

Third step: swapping

It is actually possible to swap rows. First, initial five and then ten, so ten is on the bottom row, and five will be right above it. From that point, just press the swap button.

Fourth step: addition

Let’s do some simple arithmetic operations. In addition, the order of the actual numbers won’t matter since we will eventually end up with the same sum. To add 7+2, we will press 7, then ENTER, then 2, then +. Numbers 7 and 2 will disappear from the stack, and 9 will appear on the bottom row.

Fifth step: subtraction

To do subtraction, the order in which we enter the actual numbers does matter. To subtract 7-2, we will press 7, then ENTER, then 2, then -. That will give us five. If we did 2-7, we would have minus five.

Sixth step: multiplication

To do multiplication, like with addition, the actual order doesn’t matter because it does not affect the outcome. To input 5*5, we would press 5, then ENTER, then 5, then *. Then, 25 will show up on the bottom stack.

Seventh step: division

To do division, we need to do it in order, too. Dividing 5/5 is done by inputting 5, then ENTER, then 5, then ÷. That will show us 1 on the bottom stack.