Area Polygon 

Calculate the area of a simple 2D polygon given its vertices.

API

``js
var area = require('area-polygon')
`

$3

points must consistent of points that are either of the form:

`js
{
x: Integer,
y: Integer
}
`

or

`js
[x, y]
`

The points must also trace the edge of the polygon.
The last point should return to the origin.

signed is true or false(default). If true fucntion returns the signed area of the polygon. It is helpful to determine the orientation of points in polygon. Area is positive if orientation is counter-clockwise and negative for clockwise.

Example

Calculate the area of a 4x4 square whose bottom left corner sits at the origin of the grid ([0, 0]):

`js
area([
[0, 0],
[0, 4],
[4, 4],
[4, 0]
]) === 16
``