formatiert

matrix.c

@@ -6,19 +6,17 @@
 
 Matrix createMatrix(unsigned int rows, unsigned int cols)
 {
+    Matrix m = {NULL, 0, 0};
 
-    Matrix m = {NULL, rows, cols}; // Wahrscheinlich in Programm bereits enthalten;
+    if (rows == 0 || cols == 0)
+        return m;
 
-    if (rows > 0 && cols > 0)
-    {
-        m.buffer = (MatrixType *)calloc(rows * cols, sizeof(MatrixType));
-        if (m.buffer == NULL)
-        {
-            m.rows = 0;
-            m.cols = 0;
-        }
-    }
+    m.buffer = (MatrixType *)calloc(rows * cols, sizeof(MatrixType));
+    if (m.buffer == NULL)
+        return m;
 
+    m.rows = rows;
+    m.cols = cols;
     return m;
 }
 
@@ -52,25 +50,52 @@ MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int co
 
 Matrix add(const Matrix matrix1, const Matrix matrix2)
 {
-    // test, if two matrix has exact size
-
-    if (matrix1.rows != matrix2.rows || matrix1.cols != matrix2.cols)
-        return createMatrix(0, 0);
-
-    Matrix result_add = createMatrix(matrix1.rows, matrix1.cols);
-
-    for (int r = 0; r < matrix1.rows; r++)
+    //  check, equal rows
+    // "Elementweise Addition": test, if two matrix has exact size
+    if (matrix1.rows == matrix2.rows && matrix1.cols == matrix2.cols)
     {
-        for (int c = 0; c < matrix1.cols; c++)
+        Matrix result_add = createMatrix(matrix1.rows, matrix1.cols);
+        for (int r = 0; r < matrix1.rows; r++)
         {
-            // TODO: matrix_add initialisieren
-            // matrix_add[r][c] = matrix1[r][c] + matrix2[r][c]
-
-            MatrixType sum = getMatrixAt(matrix1, r, c) + getMatrixAt(matrix2, r, c);
-            setMatrixAt(sum, result_add, r, c); // evtl re
+            for (int c = 0; c < matrix1.cols; c++)
+            {
+                // first version: matrix_add[r][c] = matrix1[r][c] + matrix2[r][c]
+                MatrixType sum = getMatrixAt(matrix1, r, c) + getMatrixAt(matrix2, r, c);
+                setMatrixAt(sum, result_add, r, c);
+            }
         }
+        return result_add;
     }
-    return result_add;
+    // "Broadcasting": matrix1 has 1 collum
+    if (matrix1.rows == matrix2.rows && matrix1.cols == 1)
+    {
+        Matrix result_add = createMatrix(matrix1.rows, matrix2.cols);
+        for (int r = 0; r < matrix1.rows; r++)
+        {
+            for (int c = 0; c < matrix2.cols; c++)
+            {
+                MatrixType sum = getMatrixAt(matrix2, r, c) + getMatrixAt(matrix1, r, 0);
+                setMatrixAt(sum, result_add, r, c);
+            }
+        }
+        return result_add;
+    }
+    // "Broadcasting": matrix2 has 1 collum
+    if (matrix1.rows == matrix2.rows && matrix2.cols == 1)
+    {
+        Matrix result_add = createMatrix(matrix1.rows, matrix1.cols);
+        for (int r = 0; r < matrix1.rows; r++)
+        {
+            for (int c = 0; c < matrix1.cols; c++)
+            {
+                MatrixType sum = getMatrixAt(matrix1, r, c) + getMatrixAt(matrix2, r, 0);
+                setMatrixAt(sum, result_add, r, c);
+            }
+        }
+        return result_add;
+    }
+
+    return createMatrix(0, 0);
 }
 
 Matrix multiply(const Matrix matrix1, const Matrix matrix2)
@@ -83,15 +108,14 @@ Matrix multiply(const Matrix matrix1, const Matrix matrix2)
 
     Matrix result_mul = createMatrix(matrix1.rows, matrix2.cols); // ""
 
-    for (int index = 0; index < matrix1.rows; index++)
+    for (unsigned int index = 0; index < matrix1.rows; index++)
     {
-        for (int shift = 0; shift < matrix2.cols; shift++)
+        for (unsigned int shift = 0; shift < matrix2.cols; shift++)
         {
             buffer_add = 0;
-            for (int skalar = 0; skalar < matrix1.cols; skalar++)
-            // TODO: matrix_add initialisieren
+            for (unsigned int skalar = 0; skalar < matrix1.cols; skalar++)
             {
-                // buffer_add += matrix1[index][skalar]*matrix2[skalar][index];
+                // buffer_add += matrix1[index][skalar]*matrix2[skalar][shift];
                 buffer_add += getMatrixAt(matrix1, index, skalar) * getMatrixAt(matrix2, skalar, shift);
             }
             // matrix_mul[index][shift] = buffer_add;