code: public void toFile(File file, Engine engine, int values, ScopeOfValues scope) throws IOException {
          toFile(file, engine, values, scope, engine.getInputVariables());
      }
docs: Saves the engine as a FuzzyLite Dataset into the specified file
  
  @param file is file to save the dataset into
  @param engine is the engine to export
  @param values is the number of values to export
  @param scope indicates the scope of the values
  @throws IOException if any error occurs upon writing to the file