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README.md

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 # Fastreach
 
-Lightweight implementation for isochrone-based reachability of public transportation networks served over an API.
-Efficiency is achieved by memory-mapping a custom pre-processed binary representation of the transportation network.
+![Build Status](https://img.shields.io/github/actions/workflow/status/Nuckal777/netex-parse/test.yaml?branch=master)
+
+Fastreach is a lightweight implementation of isochrone-based reachability for public transportation networks.
+It's designed to provide quick estimations of reachable area, while prioritizing efficiency over pinpoint accuracy.
+
+![Screenshot](docs/screenshot.jpg)
+
+## Motivation
+Isochrones are valuable tools for visualizing and understanding transportation networks and travel times.
+They are essentially lines on a map that connect points that can be reached within a specific time frame from a given starting point.
+Isochrones are particularly useful for assessing the locations that can be reached within a certain duration.
+Individuals can determine which places (offices, sights, shopping centers, etc.) are reachable from their home within a particular time frame.
+This helps planning daily activities and commuting.
+
+Additionally, combining multiple isochrones can identify strong and weak nodes of a transportation network.
+Identifying strong and weak nodes is useful for optimizing transportation networks and improving accessibility.
+
+## Usage
+The API can be started by running:
+```sh
+cargo run --bin fastreach-api --release
+```
+in the root directory of the project.
+The API expects a `graph.bin` file generated with [netex-parse](https://github.com/Nuckal777/netex-parse) binary output in its working directory.
+This can be changed by setting the `FASTREACH_GRAPH` environment variable to a desired path.
+The maximum allowed isochrone duration is set to 120 minutes and can be overwritten by setting the `FASTREACH_MAX_MINUTES` environment variable.
+
+The UI can be started by running:
+```sh
+npm install
+npm run dev
+```
+within the fastreach-ui folder.
+The `nodes.json` file generated by [netex-parse](https://github.com/Nuckal777/netex-parse) should be placed in the same folder.
+Additionally, a `docker-compose.yaml` is available.
+
+## How it works
+Fastreach models the transportation network as a graph.
+Nodes represent stations, edges vehicles with or without timetables.
+Given a duration reachable stations are determined with dijsktra's algorithm.
+For each reached station an approximate circle based on the remaining time and walking speed is created.
+These are finally merged to retrieve the reachable area.
+Efficency is achieved by memory-mapping a custom pre-processed binary representation of the transportation network.