| code_extr | Extract numeric NUTS code from the chracter | 
| EEAaq_export | Export and save an 'EEAaq_df' class object | 
| EEAaq_get_data | Download air quality data at european level from the EEA download service | 
| EEAaq_get_stations | Download EEA measurement station information dataset | 
| EEAaq_idw_map | Build a spatial interpolation map based on the Inverse Distance Weighting technique. | 
| EEAaq_import | Reverse function of 'EEAaq_export'. Reads an 'EEAaq_df' object | 
| EEAaq_map_stations | Create a map representing the stations based on the data given in input or the information specified in the parameters | 
| EEAaq_summary | Generate an 'EEAaq_df' data summary | 
| EEAaq_time_aggregate | Time aggregation of an 'EEAaq_df' class object. | 
| is_EEAaq_df | Check if a given object is an 'EEAaq_df' class object | 
| my_summarise | Aggregate data based on a specific statistic | 
| pollutants | Dataset containing information about the available pollutants | 
| stations | Air quality measurement stations information. |