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 provide the condition, ascending descending and you can use inside on sort method. No worries You are using a native javascript method with nice stability

var countryCount = d3.nest()
                    .key(function(d) { return d.Country; })
                    .rollup(function(a){return a.length;})
                    .entries(data)
                    .sort(function(a, b){ return d3.ascending(a.values, b.values); })

console.log(JSON.stringify(countryCount));