Draw a pie chart with same size pieces using dc.js

1
votes

May be my question is silly but I need to plot a pie chart using dc.js that it has years as pieces but they all need to be same size no matter group data. i got data group from crossfilter.js as same value. However i need to know that there is any other way to get pie chart with same size pieces only using dimension?

1
dc.jscrossfilter
Renaming tag - dc is a venerable desk calculator from the 70's - dc.js is the javascript dimensional charting library. - Gordon

1 Answers

0
votes

I guess that's not really a pie chart anymore. However, I'd suggest doing this with a "fake group".

First go ahead and create a group for this, even though we won't use the values, we'll let crossfilter tally up the groups.

var group = dimension.group();

Then produce a "fake group" which, each time it's read, will set all the values to 1:

function all_equal_group(group) {
    function make_equal(kvs) {
        return kvs.map(function(kv) {
            return {key: kv.key, value: 1};
        });
    }
    return {
        all: function() {
            return make_equal(group.all());
        },
        top: function(N) {
            return make_equal(group.top(N));
        }
    };
}

The top function is in case you're using capping. Maybe not needed here, but it won't hurt.

Apply it to your chart like this:

pieChart.group(all_equal_group(group));