Compute the real roots of a quadratic equation in a numerically stable manner
npm install quadratic-roots 
Compute the real roots of a quadratic equation in a numerically stable manner
In floating point arithmetic, the naive method for determining the roots of a quadratic equation ("x equals negative b, plus or minus etc.") may lead to severe cancellation and an inaccurate result.
Sample usage:
``javascript
var roots = require('quadratic-roots')
roots(0,0,0) // --> []
roots(0,0,6) // --> []
roots(0,2,6) // --> [-3]
roots(1,1,-12) // --> [-4,3]
roots(1,-4,4) // --> [2,2]
roots(1,0,1) // --> []
`
`sh`
$ npm install quadratic-roots
Returns
- If no roots, returns an empty array []`
- If a linear equation, returns one root
- If a parabola with no real roots, returns an empty array
- If a parabola with one root multiplicity 2, returns an array with the same root twice
- Otherwise returns an array with two real roots
(c) 2015 Ricky Reusser. MIT License