linerarregreession

public class LinearRegression {
    private final double intercept, slope;
    double[] previousdata= new double[]{2011,2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020};;
    double[] newyears = new double[]{2021,2022,2023,2024,2025,2026,2027,2028,2029,2030};
     /**
     * Performs a linear regression on the data points {@code (y[i], x[i])}.
     */
    public double[] LinearRegression(double[] x, double[] y) {
        if (x.length != y.length) {
            throw new IllegalArgumentException("array lengths are not equal");
        }
        int n = x.length;
        double sumx = 0.0, sumy = 0.0, sumx2 = 0.0;
        for (int i = 0; i < n; i++) {
            sumx  += x[i];
            sumx2 += x[i]*x[i];
            sumy  += y[i];
        }
        double xbar = sumx / n;
        double ybar = sumy / n;
        double xxbar = 0.0, yybar = 0.0, xybar = 0.0;
        for (int i = 0; i < n; i++) {
            xxbar += (x[i] - xbar) * (x[i] - xbar);
            xybar += (x[i] - xbar) * (y[i] - ybar);
        }
        slope  = xybar / xxbar;
        intercept = ybar - slope * xbar;
        double[] eq= new double[1];
        eq[0]=slope;
        eq[1]=intercept;
        return eq[];
        
    }
   public double[] Forcaster(double[] eq){
       double[] forcastedvalues = new double[9];
       for (int i = 0; i < 9; i++){
           forcastedvalues[i] = (eq[0]*newdata[i] + eq[1]);
        }
       return forcastedvalues[];
       
    }
}