The transit catchment area is an important concept for public transport planning. This study proposes a methodological framework to generate network-based transit catchment areas by walking. Three components of the framework, namely subgraph construction, extended shortest path tree construction and contour generation are presented step by step. Methods on how to generalize the framework to the cases of the directed road network and non-point facilities are developed. The implementation of the framework is provided as an open-source project. Using metro stations in Shanghai as a case study, we illustrate the feasibility of the proposed framework. Experiments show that the proposed method generates catchment areas of high geospatial accuracy and significantly increases computational efficiency. The open-source program can be applied to support research related to transit catchment areas and has the potential to be extended to include more routing-related factors.

中文翻译：

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通过步行生成基于网络的过境集水区的开源框架

过境集水区是公共交通规划的重要概念。本研究提出了一种通过步行生成基于网络的过境集水区的方法框架。逐步介绍了框架的三个组成部分，即子图构造，扩展的最短路径树构造和轮廓生成。研究了如何将框架归纳为有向路网和非点设施的情况的方法。该框架的实现是作为一个开源项目提供的。以上海的地铁站为例，我们说明了拟议框架的可行性。实验表明，该方法能产生高地理空间精度的集水区，大大提高了计算效率。