# Is a Point Inside or Outside a Regular Polygon?

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This Demonstration determines whether a point is inside or outside a polygon by summing the angles between adjacent vertices and the point in question. If the sum is (approximately) , the point is inside; otherwise, it is outside.

Contributed by: Jon Perry (March 2011)

Open content licensed under CC BY-NC-SA

## Snapshots

## Details

For more information, see the Wikipedia entry for Point in polygon.

## Permanent Citation

"Is a Point Inside or Outside a Regular Polygon?"

http://demonstrations.wolfram.com/IsAPointInsideOrOutsideARegularPolygon/

Wolfram Demonstrations Project

Published: March 7 2011