Fixed assert bug in SFMExample_bal

examples/SFMExample_bal.cpp

@@ -42,7 +42,9 @@ int main (int argc, char* argv[]) {
   if (argc>1) filename = string(argv[1]);
 
   // Load the SfM data from file
-  SfM_data mydata; assert(readBAL(filename, mydata));
+  SfM_data mydata;
+  const bool success = readBAL(filename, mydata);
+  assert(success);
   cout << boost::format("read %1% tracks on %2% cameras\n") % mydata.number_tracks() % mydata.number_cameras();
 
   // Create a factor graph