Aa

java/matrix/Identity.java

@@ -0,0 +1,44 @@
+public class IdentityMatrix     
+{    
+    public static void main(String[] args) {    
+        int rows, cols;    
+        boolean flag = true;    
+
+        //Initialize matrix a    
+        int a[][] = {       
+                        {1, 0, 0},    
+                        {0, 1, 0},    
+                        {0, 0, 1}    
+                    };    
+
+        //Calculates the number of rows and columns present in the given matrix    
+
+          rows = a.length;    
+        cols = a[0].length;    
+
+        //Checks whether given matrix is a square matrix or not    
+        if(rows != cols){    
+            System.out.println("Matrix should be a square matrix");    
+        }    
+        else {    
+            //Checks if diagonal elements are equal to 1 and rest of elements are 0    
+            for(int i = 0; i < rows; i++){    
+                for(int j = 0; j < cols; j++){    
+                  if(i == j && a[i][j] != 1){    
+                      flag = false;    
+                      break;    
+                  }    
+                  if(i != j && a[i][j] != 0){    
+                      flag = false;    
+                      break;    
+                  }    
+                }    
+            }    
+
+            if(flag)    
+                System.out.println("Given matrix is an identity matrix");    
+            else    
+                System.out.println("Given matrix is not an identity matrix");    
+        }    
+    }    
+}    

java/matrix/MatrixAddition.java

@@ -0,0 +1,18 @@
+public class MatrixAdditionExample{  
+public static void main(String args[]){  
+//creating two matrices    
+int a[][]={{1,3,4},{2,4,3},{3,4,5}};    
+int b[][]={{1,3,4},{2,4,3},{1,2,4}};    
+
+//creating another matrix to store the sum of two matrices    
+int c[][]=new int[3][3];  //3 rows and 3 columns  
+
+//adding and printing addition of 2 matrices    
+for(int i=0;i<3;i++){    
+for(int j=0;j<3;j++){    
+c[i][j]=a[i][j]+b[i][j];    //use - for subtraction  
+System.out.print(c[i][j]+" ");    
+}    
+System.out.println();//new line    
+}    
+}}  

java/matrix/matrixSub.java

@@ -0,0 +1,18 @@
+public class MatrixSubExample{  
+public static void main(String args[]){  
+//creating two matrices    
+int a[][]={{1,3,4},{2,4,3},{3,4,5}};    
+int b[][]={{1,3,4},{2,4,3},{1,2,4}};    
+
+//creating another matrix to store the difference of two matrices    
+int c[][]=new int[3][3];  //3 rows and 3 columns  
+
+//Subtracting and printing addition of 2 matrices    
+for(int i=0;i<3;i++){    
+for(int j=0;j<3;j++){    
+c[i][j]=a[i][j]-b[i][j];    //use - for subtraction  
+System.out.print(c[i][j]+" ");    
+}    
+System.out.println();//new line    
+}    
+}}  

java/sorting/matrixSort.java

@@ -0,0 +1,36 @@
+import java.util.*;
+
+public class Main {
+	public static void main(String[] args)
+	{
+		// Initialize the 2D vector with some values
+		List<List<Integer> > v
+			= new ArrayList<>(Arrays.asList(
+				new ArrayList<>(Arrays.asList(5, 4, 7)),
+				new ArrayList<>(Arrays.asList(1, 3, 8)),
+				new ArrayList<>(Arrays.asList(2, 9, 6))));
+
+		int n = v.size();
+		List<Integer> x = new ArrayList<>();
+		for (int i = 0; i < n; i++) {
+			for (int j = 0; j < n; j++) {
+				x.add(v.get(i).get(j));
+			}
+		}
+		Collections.sort(x);
+		int k = 0;
+		for (int i = 0; i < n; i++) {
+			for (int j = 0; j < n; j++) {
+				v.get(i).set(j, x.get(k++));
+			}
+		}
+
+		System.out.println("Sorted Matrix Will be:");
+		for (List<Integer> row : v) {
+			for (int num : row) {
+				System.out.print(num + " ");
+			}
+			System.out.println();
+		}
+	}
+}