From f0cd9abe2b63c961b843427b38baad3a99ace3c4 Mon Sep 17 00:00:00 2001
From: Giorgi Kesidis <giorgi.kesidis1@gmail.com>
Date: Mon, 10 Nov 2025 19:54:47 +0100
Subject: [PATCH] Matrix fertig

---
 matrix.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 74 insertions(+), 9 deletions(-)

diff --git a/matrix.c b/matrix.c
index 289922f..f67e8e7 100644
--- a/matrix.c
+++ b/matrix.c
@@ -1,22 +1,24 @@
 #include <stdlib.h>
 #include <string.h>
 #include "matrix.h"
+#include <stdio.h>
 
 // TODO Matrix-Funktionen implementieren
 
 Matrix createMatrix(unsigned int rows, unsigned int cols)
-{   
+{
     Matrix matrix;
     matrix.rows = rows;
     matrix.cols = cols;
 
-    matrix.data = (MatrixType *)malloc(rows* cols* sizeof(MatrixType));
+    matrix.data = (MatrixType *)malloc(rows * cols * sizeof(MatrixType));
 
-    if(matrix.data == NULL){
+    if (matrix.data == NULL)
+    {
 
         matrix.rows = 0;
         matrix.cols = 0;
-        
+
         return matrix;
     }
 
@@ -31,35 +33,98 @@ Matrix createMatrix(unsigned int rows, unsigned int cols)
 
 void clearMatrix(Matrix *matrix)
 {
-    if(matrix->data != NULL)
+    if (matrix->data != NULL)
     {
         free(matrix->data);
         matrix->data = NULL;
     }
 
     matrix->rows = 0;
-    matrix->cols =0;
-    
+    matrix->cols = 0;
 }
 
 void setMatrixAt(MatrixType value, Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
 {
-    if(rowIdx >= matrix.rows || colIdx >= matrix.cols)
+    if (rowIdx >= matrix.rows || colIdx >= matrix.cols)
     {
         fprintf(stderr, "Fehler: Ungültiger Index (%u, %u) bei Matrixgröße %u x %u\n", rowIdx, colIdx, matrix.rows, matrix.cols);
+        return; // abbruch falls fehler
     }
 
-    matrix.data[rowIdx * matrix.cols +colIdx] = value;
+    matrix.data[rowIdx * matrix.cols + colIdx] = value;
 }
 
 MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
 {
+    if (rowIdx >= matrix.rows || colIdx >= matrix.cols)
+    {
+        fprintf(stderr, "Fehler: Ungültiger Index (%u, %u) bei Matrixgröße %u x %u\n", rowIdx, colIdx, matrix.rows, matrix.cols);
+        return UNDEFINED_MATRIX_VALUE;
+    }
+
+    return matrix.data[rowIdx * matrix.cols + colIdx];
 }
 
 Matrix add(const Matrix matrix1, const Matrix matrix2)
 {
+    if (matrix1.rows != matrix2.rows || matrix1.cols != matrix2.cols)
+    {
+        fprintf(stderr, "Fehler: Matrizen haben unterschiedliche Größen (%u x %u) und (%u x %u)\n",
+                matrix1.rows, matrix1.cols, matrix2.rows, matrix2.cols);
+
+        Matrix empty = {0, 0, NULL};
+        return empty;
+    }
+
+    Matrix result = createMatrix(matrix1.rows, matrix1.cols);
+
+    if (result.data == NULL)
+    {
+        fprintf(stderr, "Fehler: Speicher konnte nicht reserviert werden!\n");
+        return result;
+    }
+
+    for (int i = 0; i < matrix1.rows; i++)
+    {
+        for (int j = 0; j < matrix1.cols; j++)
+        {
+            result.data[i * result.cols + j] = matrix1.data[i * matrix1.cols + j] + matrix2.data[i * matrix2.cols + j];
+        }
+    }
+    return result;
 }
 
 Matrix multiply(const Matrix matrix1, const Matrix matrix2)
 {
+    if (matrix1.cols != matrix2.rows)
+    {
+        fprintf(stderr, "Fehler: Matrizen der Dimension (%u x %u) und (%u x %u) koennen nicht multipliziert werden\n",
+                matrix1.rows, matrix1.cols, matrix2.rows, matrix2.cols);
+
+        Matrix empty = {0, 0, NULL};
+        return empty;
+    }
+
+    Matrix result = createMatrix(matrix1.rows, matrix2.cols);
+
+    if (result.data == NULL)
+    {
+        fprintf(stderr, "Fehler: Speicher konnte nicht reserviert werden!\n");
+        return result;
+    }
+
+    for (int i = 0; i < matrix1.rows; i++)
+    {
+        for (int j = 0; j < matrix2.cols; j++)
+        {
+            MatrixType sum = 0.0;
+
+            for (int k = 0; k < matrix1.cols; k++)
+            {
+                sum += matrix1.data[i * matrix1.cols + k] * matrix2.data[k * matrix2.cols + j];
+            }
+            result.data[i * result.cols +j] = sum;
+        }
+    }
+    return result;
 }
\ No newline at end of file