Matrix

MatrixExample.java

@@ -12,15 +12,15 @@ public static void main(String[] args) {
                 { 73, 18, 2, 2, 5, 11 }
         };
 
-        int numRows = 6;
-        int numCols = 7;
+        int numRows = 7;
+        int numCols = 6;
 
-        int[][] matrix2 = generateRandomMatrix(numRows, numCols);
+        int[][] matrix2 = generateRandomMatrix(numCols, numRows);
         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++) {
+            for (int j = 0; j < result[i].length; j++) {
                 System.out.print(result[i][j] + " ");
             }
             System.out.println();
@@ -31,8 +31,8 @@ public static void main(String[] args) {
     public static int[][] multiplyMatrices(int[][] matrix1, int[][] matrix2) {
         int rows1 = matrix1.length;
         int cols1 = matrix1[0].length;
-        int rows2 = matrix2.length;
-        int cols2 = matrix2[0].length;
+        int rows2 = matrix2[0].length;
+        int cols2 = matrix2.length;
 
         if (cols1 != rows2) {
             throw new IllegalArgumentException(
@@ -44,7 +44,7 @@ public static int[][] multiplyMatrices(int[][] matrix1, int[][] matrix2) {
 
         // 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 j = 0; j < cols1; j++) {
                 for (int k = 0; k < cols1; k++) {
                     result[j][k] += matrix1[i][j] * matrix2[k][j];
                 }

MatrixExampleTester.java

@@ -0,0 +1,35 @@
+import java.util.Arrays;
+
+public class MatrixExampleTester {
+    public static void main(String[] args) {
+        // int[][] one = MatrixExample.generateRandomMatrix(5, 5);
+        // int[][] two = MatrixExample.generateRandomMatrix(5, 5);
+        // int[][] multiplied = MatrixExample.multiplyMatrices(one, two);
+        // System.out.println(Arrays.deepToString(multiplied));
+
+        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 = 7;
+        int numCols = 6;
+
+        int[][] matrix2 = MatrixExample.generateRandomMatrix(numRows, numCols);
+        int[][] result = MatrixExample.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; j++) {
+                System.out.print(result[i][j] + " ");
+            }
+            System.out.println();
+        }
+
+    }
+}