Anyone know a way to shorten my code.

If you want to know, this code finds roots of polynomials.

import java.util.*;

class Roots {

      public static void main( String[] args ){
            double L, R;
            double resolution = 0.01;
            double tolerance = 0.0000001;
            double threshold = 0.001;

            int polyRootPointer = 0;
            int diffRootPointer = 0;

            boolean root = false;

            Scanner sc = new Scanner(System.in);


            System.out.print("Enter the degree: ");
            degree = sc.nextInt();
            coefNum = degree + 1;
            System.out.print("Enter " + coefNum + " coefficients: ");
            double[] coefficients = new double[coefNum];
            polyArray = new double[coefNum];
            double[] polyRootArray = new double[degree];
            diffArray = new double[coefNum];
            double[] diffRootArray = new double[degree];
            for(int i = 0; i < coefNum; i++) {
                  coefficients[i] = sc.nextDouble();
            }
            System.out.print("Enter the left and right endpoints: ");
            L = sc.nextDouble();
            R = sc.nextDouble();

            System.out.println();

            diff(coefficients);

            for (double i = L; i < R-resolution; i = i + resolution){
                  if (isPositive(diffArray, i) != isPositive(diffArray, i+resolution) || isPositive(diffArray, i) == 0) {
                        diffRootArray[diffRootPointer] = findRoot(diffArray, i, i+resolution, tolerance);
                        diffRootPointer++;
                  }
            }

            for (int i = 0; i < diffRootArray.length; i++) {
                  double tempValue;
                  tempValue = poly(coefficients, diffRootArray[i]);
                  tempValue = Math.abs(tempValue);
                  if (tempValue < threshold) {
                        polyRootArray[polyRootPointer] = diffRootArray[i];
                        polyRootPointer++;
                        root = true;
                  }
            }

            for (double i = L; i < R-resolution; i = i + resolution){
                  if (isPositive(coefficients, i) != isPositive(coefficients, i+resolution) || isPositive(coefficients, i) == 0) {
                        polyRootArray[polyRootPointer] = findRoot(coefficients, i, i+resolution, tolerance);
                        polyRootPointer++;
                        root = true;
                  }
            }

            Arrays.sort(polyRootArray);

            if (root == true) {
                  for (int i = 0; i < polyRootArray.length; i++) {
                        if (polyRootArray[i] != 0.0) {
                              System.out.printf("Root found at %.5f%n", polyRootArray[i]);
                        }
                  }
            } else {
                  System.out.println("No roots were found.");
            }
      }

      public static int degree;
      public static double[] polyArray;
      public static double[] diffArray;
     public static int coefNum;

           static double poly(double[] C, double x){
            double Sum = 0;
            polyArray[0] = C[0];
            for (int i = 1; i < polyArray.length; i++){
                  polyArray[i] = C[i]*(Math.pow(x, i));
            }
            for (int i = 0; i < polyArray.length; i++){
                  Sum = Sum + polyArray[i];
            }
            return(Sum);

      }

      static double[] diff(double[] C){
            for (int i = 0; i < degree; i++){
                  diffArray[i] = (i+1)*C[i+1];
            }
            return(diffArray);
      }

      static double findRoot(double[] C, double a, double b, double tolerance){
            double root = 0.0 , residual;
            while ( Math.abs(b - a) > tolerance ) {
                  root = (a + b) / 2.0;
                  residual = poly(C, root);
                  if (poly(C, a) > 0 && poly(C, b) < 0) {
                        if (residual > 0)
                              a = root;
                        else
                              b = root;
                  } else if (poly(C, a) < 0 && poly(C, b) > 0) {
                        if (residual > 0)
                              b = root;
                        else
                              a = root;
                  }
            }
            return(root);
      }
      static int isPositive(double[] C, double a){
            double endpointTempA;
            endpointTempA = poly(C, a);
            if (endpointTempA < 0) {
                  return(1);
            } else if (endpointTempA > 0) {
                  return(2);
            } else {
                  return(0);
            }
      }
}

Code (markup):

This code works so you guys know, so you don't have to help me with errors.

 

This forum is about JAVASCRIPT not JAVA so you know, so you probably won't get help here.