How do I create a best-fit polynomial curve in Javascript?

Question

I\'m trying to calculate a best-fit curve for data using a 3-6 order polynomial. I found this tutorial: Cubic Regression (best fit line) in JavaScript

First, I can\'t

Answer 1

Figured it out using Matrix Algebra:

var x = [500,1000,1500,2000,2500,3000,3500,4000,4500,5000,5500,6000,6500,7000];
var y = [50,80,100,160,210,265,340,390,440,470,500,500,495,460];

order = 3;

var xMatrix = [];
var xTemp = [];
var yMatrix = numeric.transpose([y]);

for (j=0;j<x.length;j++)
{
    xTemp = [];
    for(i=0;i<=order;i++)
    {
        xTemp.push(1*Math.pow(x[j],i));
    }
    xMatrix.push(xTemp);
}

var xMatrixT = numeric.transpose(xMatrix);
var dot1 = numeric.dot(xMatrixT,xMatrix);
var dotInv = numeric.inv(dot1);
var dot2 = numeric.dot(xMatrixT,yMatrix);
var solution = numeric.dot(dotInv,dot2);
console.log("Coefficients a + bx^1 + cx^2...")
console.log(solution);

jsbin: http://jsbin.com/yoqiqanofo/1/