## Complex Calculator

**What is it:** A calculator that operates on complex numbers.
There are actually two versions: the basic calculator and the stack calculator.

**How it works:**The **basic calculator.** You type in two complex numbers, *x* and *y*,
in either rectangular or polar coordinates. Then you click on an operation (addition,
subtraction, multiplication, division, exponentiation or reciprocal) to produce a third
complex number *z*.
The calculator displays all three numbers in both polar and rectangular coordinates.

The **stack calculator** maintains a stack of complex numbers. When you type a complex
number into the calculator it is put at the end (bottom) of the stack. When you do an operation,
it is done on the last two complex numbers on the stack (called *x* and *y*),
and the result is also put on the stack. The great thing about the stack is that chain
calculations are easy to do because you can recall any of the numbers that are already
on the stack.

Another feature is that each complex number that you enter can be given a text
description. When you carry out an operation the result is automatically given
a text description as well, based on the operands and the operation. In the example below
we entered two numbers with the descriptions ‘Zab’ and ‘i3’.
When we multiplied them the result was given the description ‘Zab*i3’. Another
feature is that the contents of the stack can be pasted into a word processor.

**Where to now?**