Question

Can someone please explain the difference between datum() and data() in D3.js? I see both being used and I am not sure why you should choose one over the other?

Answer 1

I found the correct answer here from Mike himself:

D3 – how to deal with JSON data structures?

If you want to bind your data to a single SVG element, use

(...).data([data])

or

(...).datum(data)

If you want to bind your data to multiple SVG elements

(...).data(data).enter().append("svg")

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