Let's go through an example creating a calendar heat map chart from Google. I would suggest you start by reviewing my overview blog post and then the Developer Guide provided by IBM. The guide takes you through an example step by step with quite a bit of detailed information. The example uses a simple D3 chart, which works great for getting started, but it takes quite a bit of D3 knowledge to build anything more complex. It has a ton of flexibility but also a pretty difficult learning curve. Cognos allows you to use any JavaScript based chart library, so I started looking around for something a little simpler and came across Google Charts. They don't offer near the flexibility of D3, but there are quite a few options that have a variety of configuration properties that can be used, and they are significantly easier to incorporate.
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