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docs: https://developers.google.com/chart/interactive/docs/index
examples: https://developers.google.com/chart/interactive/docs/gallery
Charts.js
6 chart types
nice animations; very tin js, leverages HTML5 canvas + cross platform fallback
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project: http://d3js.org
code: https://github.com/mbostock/d3
drupal module: https://www.drupal.org/project/d3
API: https://github.com/mbostock/d3/wiki/API-Reference
examples: https://github.com/mbostock/d3/wiki/Gallery
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