HopfieldNetwork

import java.util.*;

public class HopfieldNetwork {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter the number of input patterns: ");
        int n = sc.nextInt();
        int s[][] = new int[n][];
        System.out.println("Enter the length of the inputs: ");
        int length = sc.nextInt();
        for (int i = 0; i < s.length; i++) {
            s[i] = new int[length];
            System.out.println("Enter the pattern for s" + (i + 1) + ":");
            for (int j = 0; j < s[i].length; j++) {
                s[i][j] = sc.nextInt();
            }
        }
        int[][] weights = new int[length][length];
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < length; j++) {
                for (int k = 0; k < length; k++) {
                    weights[j][k] += (s[i][j] * s[i][k]);
                }
            }
        }
        System.out.println("Making the diagonal elements as 0: ");
        for (int i = 0; i < weights.length; i++) {
            weights[i][i] = 0;
        }
        System.out.println("The weight matrix is: ");
        for (int i = 0; i < weights.length; i++) {
            System.out.println(Arrays.toString(weights[i]));
        }
        for (int i = 0; i < n; i++) {
            int inter[][] = new int[n][length];
            System.out.println("Now we will calculate WP" + i + "");
            for (int j = 0; j < length; j++) {

                for (int k = 0; k < length; k++) {
                    inter[i][k] += weights[k][j] * s[i][j];
                }
            }
            for (int p = 0; p < length; p++) {
                inter[i][p] = inter[i][p] / (Math.abs(inter[i][p]));
            }
            System.out.println("Output for pattern " + (i + 1) + " is: " + Arrays.toString(inter[i]));
        }
    }
}


/*
bash-4.1$ javac HopfieldNetwork.java
bash-4.1$ java HopfieldNetwork
Enter the number of input patterns:
3
Enter the length of the inputs:
6
Enter the pattern for s1:
1 1 1 -1 -1 -1
Enter the pattern for s2:
-1 -1 -1 1 1 1
Enter the pattern for s3:
1 1 -1 -1 1 1
Making the diagonal elements as 0:
The weight matrix is:
[0, 3, 1, -3, -1, -1]
[3, 0, 1, -3, -1, -1]
[1, 1, 0, -1, -3, -3]
[-3, -3, -1, 0, 1, 1]
[-1, -1, -3, 1, 0, 3]
[-1, -1, -3, 1, 3, 0]
Now we will calculate WP0
Output for pattern 1 is: [1, 1, 1, -1, -1, -1]
Now we will calculate WP1
Output for pattern 2 is: [-1, -1, -1, 1, 1, 1]
Now we will calculate WP2
Output for pattern 3 is: [1, 1, -1, -1, 1, 1]




bash-4.1$ java HopfieldNetwork
Enter the number of input patterns:
4
Enter the length of the inputs:
4
Enter the pattern for s1:
1 -1 1 -1
Enter the pattern for s2:
-1 1 -1 1
Enter the pattern for s3:
1 1 -1 -1
Enter the pattern for s4:
-1 -1 1 1
Making the diagonal elements as 0:
The weight matrix is:
[0, 0, 0, -4]
[0, 0, -4, 0]
[0, -4, 0, 0]
[-4, 0, 0, 0]
Now we will calculate WP0
Output for pattern 1 is: [1, -1, 1, -1]
Now we will calculate WP1
Output for pattern 2 is: [-1, 1, -1, 1]
Now we will calculate WP2
Output for pattern 3 is: [1, 1, -1, -1]
Now we will calculate WP3
Output for pattern 4 is: [-1, -1, 1, 1]



*/