multiply, besteht MatrixTests

matrix.c

@@ -162,9 +162,27 @@ Matrix add(const Matrix matrix1, const Matrix matrix2) {
     Matrix errorMatrix = {0, 0, NULL};
     return errorMatrix;
   }
-
- 
-
   return result;
 }
-Matrix multiply(const Matrix matrix1, const Matrix matrix2) { return matrix1; }
+Matrix multiply(const Matrix matrix1, const Matrix matrix2) { 
+  //Spalten1 müssen gleich zeilen2 sein! dann multiplizieren
+  if (matrix1.cols == matrix2.rows){
+    Matrix multMatrix = createMatrix(matrix1.rows,matrix2.cols);
+    for (int r=0; r< matrix1.rows; r++){
+      for (int c=0; c< matrix2.cols; c++){
+        MatrixType sum = 0.0;
+        for (int k=0; k< matrix1.cols; k++){
+          sum+= matrix1.buffer[r*matrix1.cols+k]*matrix2.buffer[k*matrix2.cols+c];
+        }
+        multMatrix.buffer[r*multMatrix.cols+c] = sum;
+      }
+    }
+    return multMatrix;
+  }
+  //sonst fehler
+  else{
+    Matrix errorMatrix = {0, 0, NULL};
+    return errorMatrix;
+  }
+  //return matrix1;
+}