compare-angle

compare-angle
=============
Let A, B, C and D be four points in the plan. Then of the pair of angles ABC and ABD, determine which is larger.

``
C
* D
\ *
\ABC/
\ / ABD
-------------
B A
`

Example
=======

`javascript
var compareAngle = require("compare-angle")

var A = [2, 0]
var B = [0, 0]
var C = [-1, 2]
var D = [1, 1]

console.log(compareAngle(A, B, C, D), compareAngle(A, B, D, C))
`

Output:

`
1 -1
`

Install
=======

`
npm install compare-angle
`

API
===

#### require("compare-angle")(a, b, c, d)
Compares the angles ABC and ABD to determine which is greater.

* a, b are the base points of the angle
* c is the end of the first angle
* d is the end of the second angle

Returns A number indicating which angle is larger

* +1 if angle ABC is greater than angle ABD
* 0 if the angles are equal
* -1` if angle ABD is greater than angle ABC

Credits
=======
(c) 2014 Mikola Lysenko. MIT License