d3.js sorting by rollup field

Question

I am having a JSON data and i want to group by a field and then sort by the count.

var data = [{\"Name\":\"Ravi\",\"Country\":\"India\"},
            {\"Name\":         


        

Answer 1

d3 provides a method sortKeys in nest function which will sort your nested list based on the key you selected. You can pass d3.ascending or d3.descending based on your requirement.

From your example:

var countryCount = d3.nest()
                    .key(function(d) { return d.Country; })
                    .sortKeys(d3.ascending)
                    .entries(data);

which will give you:

[{"key":"India","values":4},{"key":"UK","values":3},{"key":"USA","values":1}]