City Transport Analyzer: A Powerful Qgis Plugin For Public Transport Accessibility And Intermodality Analysis

Abstract. This study presents the City Transport Analyzer (CTA) QGIS plug-in designed for analyzing urban public transportation (PT) networks, exploiting GTFS data to investigate their multimodal nature. GTFS, a standardized format for PT schedules and geographic information, enables accurate data sharing, crucial for service analysis. The plug-in extracts GTFS data and converts it into GIS layers for analysis. It constructs a graph data structure using NetworkX, representing PT routes, with edges indicating travel time and transport type. Two key analyses are conducted: Service Area for accessibility and Nearby Stops Path for intermodality. The accessibility analysis determines reachable areas within specified time frames via PT and walking from one or more source points. It provides comprehensive insights into service coverage and the potential reach of PT networks within urban areas. The intermodality analysis assesses street paths for modal changes beyond PT nodes, offering valuable information on connectivity and potential PT usage patterns. Tested on case studies in Milan and Rio de Janeiro, the plug-in demonstrates utility in understanding metropolitan PT networks, but also room for improving the overall accuracy, usability and performances of the tool. The CTA plugin offers a flexible and user-friendly tool for studying service coverage, accessibility, and connectivity, aiding urban infrastructure analysis and planning. Future work aims to extend analyses to the whole city, including other city contexts. Ultimately, the CTA plugin contributes to a deeper understanding of urban PT networks and areas, facilitating informed decision-making in urban planning and infrastructure management.