From 82c335ca893cbfe7aaecc5b4512b2b8be89423bf Mon Sep 17 00:00:00 2001
From: = <markus.kob@outlook.com>
Date: Tue, 25 Nov 2025 15:01:21 +0100
Subject: [PATCH] Fixed UnitTest Errorrs in matrix.c

---
 matrix.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/matrix.c b/matrix.c
index 3552da8..ba4b374 100644
--- a/matrix.c
+++ b/matrix.c
@@ -75,25 +75,30 @@ void clearMatrix(Matrix *matrix)
 {
     for (int i = 0; i < matrix->rows; i++) {
         for (int j = 0; j < matrix->cols;j++) {
-            matrix->buffer[i + matrix->rows* j] = UNDEFINED_MATRIX_VALUE;
+            matrix->buffer[i + matrix->rows * j] = UNDEFINED_MATRIX_VALUE;
         }
     }
     free(matrix->buffer);
     matrix->rows = 0;
     matrix->cols = 0;
-    
+    matrix->buffer = NULL;
 }
 
 void setMatrixAt(MatrixType value, Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
 {
-    matrix.buffer[rowIdx-1 + matrix.rows*(colIdx-1)] = value;
+    //checks, if the given incies are allowed
+    if((rowIdx) < matrix.rows && (colIdx) < matrix.cols) matrix.buffer[rowIdx + matrix.rows*(colIdx)] = value;
 }
 
 MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
 {
-    MatrixType returnVal;
-    returnVal = matrix.buffer[rowIdx-1 + matrix.rows*(colIdx-1)];
-    return returnVal;
+    //checks, if the given indices are allowed
+    if((rowIdx) < matrix.rows && (colIdx) < matrix.cols) {
+        MatrixType returnVal;
+        returnVal = matrix.buffer[rowIdx + matrix.rows*(colIdx)];
+        return returnVal;
+    }
+    else return 0;
 }
 
 Matrix add(const Matrix matrix1, const Matrix matrix2)
@@ -101,7 +106,8 @@ Matrix add(const Matrix matrix1, const Matrix matrix2)
     //check if the matrices are able to be added (same size)
     if (matrix1.cols == matrix2.cols && matrix1.rows == matrix2.rows){
         //size of the matrices should be the same, if the addition is supposed to happen
-        Matrix outputMatrix = createMatrix(matrix1.rows, matrix1.cols);
+        // Matrix outputMatrix = createMatrix(matrix1.rows, matrix1.cols);
+        Matrix outputMatrix = createMatrix(matrix1.cols, matrix1.rows);
         for (int i = 0; i < matrix1.rows;i++) {
             for (int j = 0; j < matrix1.cols; j++) {
                 // how this should work in normal Matrix version:
@@ -125,13 +131,14 @@ Matrix multiply(const Matrix matrix1, const Matrix matrix2)
 {
     //check, if the matrices can be multiplied
     if (matrix1.rows == matrix2.cols) {
-        Matrix outputMatrix = createMatrix(matrix1.rows, matrix2.cols);
+        // Matrix outputMatrix = createMatrix(matrix1.rows, matrix2.cols);
+        Matrix outputMatrix = createMatrix(matrix2.cols, matrix1.rows);
         for(int i = 0; i < matrix1.rows; i++) {
             for (int j = 0; j < matrix2.cols; j++) {
                 for (int k = 0; k < matrix2.rows; k++) {
                     // how this should work in normal Matrix version:
                     // outputMatrix.buffer[i][j] = matrix1.buffer[i][k] * matrix2.buffer[k][j];
-                    outputMatrix.buffer[i + outputMatrix.rows* j] = matrix1.buffer[i + matrix1.rows* k] * matrix2.buffer[k + matrix2.rows*j];
+                    outputMatrix.buffer[i + outputMatrix.rows * j] = matrix1.buffer[i + matrix1.rows * k] * matrix2.buffer[k + matrix2.rows * j];
                 }
             }
         }