(0.4.1): Added a Tester File

MatrixExample.java

@@ -1,33 +1,6 @@
 import java.util.Random;
 
 public class MatrixExample {
-    public static void main(String[] args) {
-        int[][] matrix = {
-                { 1, 2, 3, 4, 5, 6 },
-                { 4, 5, 6, 3, 7, 2 },
-                { 27, 8, 9, 5, 3, 21 },
-                { 73, 2, 19, 5, 1, 8 },
-                { 47, 9, 9, 5, 0, 22 },
-                { 78, 86, 1, 4, 1, 21 },
-                { 73, 18, 2, 2, 5, 11 }
-        };
-
-        int numRows = 6;
-        int numCols = 7;
-
-        int[][] matrix2 = generateRandomMatrix(numRows, numCols);
-        int[][] result = multiplyMatrices(matrix, matrix2);
-
-        System.out.println("result length: " + result.length + " x " + result[0].length);
-        for (int i = 0; i < result.length; i++) {
-            for (int j = 0; j < result[i].length; i++) {
-                System.out.print(result[i][j] + " ");
-            }
-            System.out.println();
-        }
-
-    }
-
     public static int[][] multiplyMatrices(int[][] matrix1, int[][] matrix2) {
         int rows1 = matrix1.length;
         int cols1 = matrix1[0].length;
@@ -37,21 +10,26 @@ public static int[][] multiplyMatrices(int[][] matrix1, int[][] matrix2) {
         if (cols1 != rows2) {
             throw new IllegalArgumentException(
                     "Number of columns in the first matrix must be equal to the number of rows in the second matrix.");
+
         }
 
         // Some more issues here too
-        int[][] result = new int[rows1+1][cols2+1];
+        int[][] result = new int[rows1][cols2];
 
         // Lots of issues with this code, it used to be working perfectly though
-        for (int i = 0; i < rows1; i++) {
-            for (int j = 0; j < cols2; j++) {
-                for (int k = 0; k < cols1; k++) {
-                    result[j][k] += matrix1[i][j] * matrix2[k][j];
+        for (int i = 0; i < rows1; i++) { // matrix 1 rows
+            for (int j = 0; j < cols1; j++) { // columns
+                for (int k = 0; k < cols2; k++) {
+                    result[i][k] += matrix1[i][j] * matrix2[j][k];
+
                 }
+
             }
+
         }
 
         return result;
+
     }
 
     public static int[][] generateRandomMatrix(int numRows, int numCols) {
@@ -61,10 +39,13 @@ public static int[][] generateRandomMatrix(int numRows, int numCols) {
         for (int i = 0; i < numRows; i++) {
             for (int j = 0; j < numCols; j++) {
                 matrix[i][j] = random.nextInt(100); // Generates random values between 0 and 99
+
             }
+
         }
 
         return matrix;
+
     }
 
 }

MatrixExampleTester.java

@@ -0,0 +1,82 @@
+public class MatrixExampleTester {
+    public static void main(String[] args) {
+        int[][] matrix = {
+                { 1, 2, 3, 4, 5, 6 },
+                { 4, 5, 6, 3, 7, 2 },
+                { 27, 8, 9, 5, 3, 21 },
+                { 73, 2, 19, 5, 1, 8 },
+                { 47, 9, 9, 5, 0, 22 },
+                { 78, 86, 1, 4, 1, 21 },
+                { 73, 18, 2, 2, 5, 11 }
+        };
+
+        int[][] test1 = {
+            { 1, 2, 3 },
+            { 4, 5, 6 },
+            { 7, 8, 9 }
+        };
+
+        int[][] test2 = {
+            { 1, 2, 3 },
+            { 4, 5, 6 },
+            { 7, 8, 9 }
+        };
+
+        // GenerateRandomMatrix
+        System.out.println("==generateRandomMatrix()==");
+        int numRows = 6;
+        int numCols = 7;
+
+        int[][] matrix2 = MatrixExample.generateRandomMatrix(numRows, numCols);
+        System.out.println(matrix2);
+
+        // print it out
+        System.out.println("result length: " + matrix2.length + " x " + matrix2[0].length);
+        for (int i = 0; i < matrix2.length; i++) {
+            for (int j = 0; j < matrix2[i].length; j++) {
+                System.out.print(matrix2[i][j] + " ");
+
+            }
+
+            System.out.println();
+
+        }
+
+        System.out.println("");
+
+        // multiplyMatricies
+        System.out.println("==multiplyMatricies()==");
+        int[][] result1 = MatrixExample.multiplyMatrices(matrix, matrix2);
+        int[][] result2 = MatrixExample.multiplyMatrices(test1, test2);
+
+        // result 1
+        System.out.println("result length: " + result1.length + " x " + result1[0].length);
+        for (int i = 0; i < result1.length; i++) {
+            for (int j = 0; j < result1[i].length; j++) {
+                System.out.print(result1[i][j] + " ");
+
+            }
+
+            System.out.println();
+
+        }
+
+        System.out.println();
+
+        // result 2
+        System.out.println("result length: " + result2.length + " x " + result2[0].length);
+        for (int i = 0; i < result2.length; i++) {
+            for (int j = 0; j < result2[i].length; j++) {
+                System.out.print(result2[i][j] + " ");
+
+            }
+
+            System.out.println();
+
+        }
+
+        System.out.println();
+
+    }
+
+}