code: function nevillesIteratedInterpolation (x, X, Y) {
    var Q = [Y]
    for (var i = 1; i < X.length; i++) {
      Q.push([])
      for (var j = 1; j <= i; j++) {
        Q[j][i] = ((x-X[i-j])*Q[j-1][i] - (x-X[i])*Q[j-1][i-1])/( X[i] - X[i-j] )
      }
    }
    return Q[j-1][i-1]
  }
docs: Neville's Iterated Interpolation algorithm implementation
  http://en.wikipedia.org/wiki/Neville's_algorithm <- for reference
  
  @param {Number} x                           number for which polynomial is calculated
  @param {Array} X                            set of distinct x values
  @param {Array} Y                            set of distinct y=f(x) values
  @returns {number}                           interpolating polynomial