read data                                                                                                                                                             
                                                                                                                                                                                                                            
                                                                                                                                                                                                                            
                                                                                                                                                                                                                            
                                                                                                                                                                                                                            
                                                                                                                                                                                                                            
                          generate diagrams                                                                                                                                                                                 
                                                                                                                                                                                                                            
                                                                                                                                                                                                                            
                                                                                                                                                                                                                            
                                                      more data?                                                                                                                yes