Nonconvex

The term complex polygon can mean two different things:

In geometry, a complex polygon is a polygon in the complex Hilbert plane, which has two complex dimensions.

A complex number may be represented in the form ${\displaystyle (a+ib)}$, where ${\displaystyle a}$ and ${\displaystyle b}$ are real numbers, and ${\displaystyle i}$ is the square root of ${\displaystyle -1}$. Multiples of ${\displaystyle i}$ such as ${\displaystyle ib}$ are called imaginary numbers. A complex number lies in a complex plane having one real and one imaginary dimension, which may be represented as an Argand diagram. So a single complex dimension comprises two spatial dimensions, but of different kinds - one real and the other imaginary.

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