tweaks

.gitignore

@@ -38,6 +38,7 @@
 Startcode/mnist
 Startcode/runTests
 Startcode/runMatrixTests
+Startcode/runImageInputTests
 Startcode/runNeuralNetworkTests
 
 # clangd (locally generated, contains absolute paths)

Startcode/neuralNetwork.c

@@ -180,6 +180,9 @@ static void writeDimension(FILE *file, const unsigned int dimension)
 
 static void writeMatrix(FILE *file, const Matrix matrix)
 {
+    if (matrix.buffer == NULL) 
+        return;
+
     fwrite(matrix.buffer, sizeof(MatrixType), matrix.rows * matrix.cols, file);
 }