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CollisionViz is a data visualization web app for motor vehicle collisions in New York City. It is built with

How to Use

  1. Select the date. The app will load all the collisions on that day from NYPD API, and show a time distribution chart and a heatmap.
  2. The app also shows markers for collisions that happened during 8AM-9AM. Click on the chart to change the hour. Click on a marker for collision details.

How to Develop

  1. npm install: installs node_modules and also builds development version of bundle.js and main.css, which can also be generated with npx webpack and npx sass src/scss/main.scss main.css
  2. NODE_ENV=production npx webpack: builds production / minified version of bundle.js
  3. npm start: webpack watches jsx file changes
  4. Open index.html in browser to see the app.
  5. npm audit fix to fix security issues in node modules.

Recent Changes

  • 8/2/2020: updated dependencies
  • 3/16/2020: major update
    • Add
      • adaptors for third party APIs
    • Change
      • reorganize files and directories
    • Remove - less is more
      • play/pause mechanism
      • custom crash icons
      • map layers
      • Redux

Future Work

  • get date and time from URL query params
  • use GitHub Actions to run npm start whenever master branch is updated, so that bundle.js does not have to be in this repo.