CODEWITHSUNDEEP
javascriptjsoncsvd3.js
sir_thursday
sir_thursday

Reputation: 5409

JSON format for d3 Choropleth

I'm using d3Queue with a d3 Choropleth. When my data is in CSV format, it works fine:

CSV Data:

state, count
1, 100
2, 200
3, 300

and 

.defer(d3.csv, data, function(d) {
  rateById.set(d.state, +d.count); 
})

However, now my data is in JSON format.

JSON Data:

[
  {
    state: 1,
    count: 100
  },
  {
    state: 2,
    count: 200
  }
]

And I changed my .defer to this:

.defer(d3.json, data, function(d) {
  rateById.set(d.state, +d.count); 
})

But it is throwing the error: "Cannot read property 'state' of null". Does this mean the data is not being passed through, or that I'm messing up reading the JSON?

Upvotes: 0

Views: 187

Answers (1)

m.casey
m.casey

Reputation: 2599

Reading over the queue.js API, it looks like this should work:

.defer(d3.json, data) // .defer(task, [arguments]);
.await(function(d) { 
    rateById.set(d.state, +d.count); 
}); // .await(callback)

Link to the documentation

Upvotes: 1

Related Questions