fix: syntax

Startcode/matrix.c

@@ -4,32 +4,101 @@
 
 // TODO Matrix-Funktionen implementieren
 
+int getMatrixIndex(unsigned int cols, unsigned int rowIdx, unsigned int colIdx)
+{
+    return rowIdx * cols + colIdx;
+}
+
 Matrix createMatrix(unsigned int rows, unsigned int cols)
 {
-    
+    Matrix* m = malloc(sizeof(Matrix));
+    m->rows = rows;
+    m->cols = cols;
+    m->storage = malloc(rows * cols * sizeof(MatrixType));
+    return m;
 }
 
 void clearMatrix(Matrix *matrix)
 {
-    
+    for (unsigned int i = 0; i < matrix->rows; i++)
+    {
+        for (unsigned int j = 0; j < matrix->cols; j++)
+        {
+            setMatrixElement(matrix, i, j, UNDEFINED_MATRIX_VALUE);
+        }
+    }
 }
 
 void setMatrixAt(MatrixType value, Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
 {
-    
+    matrix.storage[getMatrixIndex(matrix.cols, rowIdx, colIdx)] = value;
 }
 
 MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
 {
-    
+    return matrix.storage[getMatrixIndex(matrix.cols, rowIdx, colIdx)];
 }
 
 Matrix add(const Matrix matrix1, const Matrix matrix2)
 {
-    
+    if (matrix1.rows != matrix2.rows || matrix1.cols != matrix2.cols)
+    {
+        fprintf(stderr, "Fehler: Dimensionen stimmen nicht überein (%ux%u und %ux%u)\n",
+                matrix1.rows, matrix1.cols, matrix2.rows, matrix2.cols);
+        return (Matrix){ .rows = 0, .cols = 0, .storage = NULL };
+    }
+
+    Matrix result = createMatrix(matrix1.rows, matrix1.cols);
+
+    // check, ob genügend Speicher vorhanden
+    if (result.storage == NULL) {
+        return (Matrix){ .rows = 0, .cols = 0, .storage = NULL };
+    }
+
+    for (unsigned int i = 0; i < matrix1.rows; i++)
+    {
+        for (unsigned int j = 0; j < matrix1.cols; j++)
+        {
+            unsigned int index = getMatrixIndex(matrix1.cols, i, j);
+            result.storage[index] = matrix1.storage[index] + matrix2.storage[index];
+        }
+    }
+
+    return result;
 }
 
 Matrix multiply(const Matrix matrix1, const Matrix matrix2)
 {
-    
+    if (matrix1.cols != matrix2.rows)
+    {
+        fprintf(stderr, "Fehler: Spalten von Matrix 1 (%u) entsprechen nicht Zeilen von Matrix 2 (%u)\n",
+                matrix1.cols, matrix2.rows);
+        return (Matrix){ .rows = 0, .cols = 0, .storage = NULL };
+    }
+
+    Matrix result = createMatrix(matrix1.rows, matrix2.cols);
+
+    // check, ob genügend Speicher vorhanden
+    if (result.storage == NULL) {
+        return (Matrix){ .rows = 0, .cols = 0, .storage = NULL };
+    }
+
+    for (unsigned int i = 0; i < matrix1.rows; i++)
+    {
+        for (unsigned int j = 0; j < matrix2.cols; j++)
+        {
+            MatrixType sum = 0;
+
+            for (unsigned int k = 0; k < matrix1.cols; k++)
+            {
+                MatrixType val1 = matrix1.storage[i * matrix1.cols + k];
+                MatrixType val2 = matrix2.storage[k * matrix2.cols + j];
+                sum += val1 * val2;
+            }
+
+            result.storage[i * result.cols + j] = sum;
+        }
+    }
+
+    return result;
 }

Startcode/matrix.h

@@ -6,7 +6,13 @@
 typedef float MatrixType;
 
 // TODO Matrixtyp definieren
+// Flat Storage: Nur ein Pointer, sorgt für zusammenhängendes array, kein verstreuter Speicher -> bessere Performance
+typedef struct {
+    unsigned int rows;
+    unsigned int cols;
 
+    MatrixType* storage;
+} Matrix;
 
 Matrix createMatrix(unsigned int rows, unsigned int cols);
 void clearMatrix(Matrix *matrix);