Using techanJS D3 examples with JSON data

Question

I what to use a couple of the techanJS examples in my application but am struggling use my own data.

Here is the example code for the close chart which I want to use.

I have a play! framework application which passes in a List[CloseList] array, this is then converted to a JSON object using:

var closesJSON = @{Html(new Gson().toJson(closes))};

I am then assuming that I will be able to replace d3.csv() with d3.json() but cannot find a working example and my hacking hasn't got me anywhere so far.

d3.csv("data.csv", function(error, data) {
    var accessor = close.accessor();

    data = data.slice(0, 200).map(function(d) {
        return {
            date: parseDate(d.Date),
            open: +d.Open,
            high: +d.High,
            low: +d.Low,
            close: +d.Close,
            volume: +d.Volume
        };
    }).sort(function(a, b) { return d3.ascending(accessor.d(a), accessor.d(b)); });

    x.domain(data.map(accessor.d));
    y.domain(techan.scale.plot.ohlc(data, accessor).domain());

    svg.append("g")
            .datum(data)
            .attr("class", "close")
            .call(close);

    svg.append("g")
            .attr("class", "x axis")
            .attr("transform", "translate(0," + height + ")")
            .call(xAxis);

    svg.append("g")
            .attr("class", "y axis")
            .call(yAxis)
            .append("text")
            .attr("transform", "rotate(-90)")
            .attr("y", 6)
            .attr("dy", ".71em")
            .style("text-anchor", "end")
            .text("Price ($)");
});

Working code here, this renders:

d3.json("/api/closedata/@equity.getId", function(error, data) {
    var accessor = close.accessor();

    data = data.map(function(d,i) {
        console.log(d.high);
        return {
            date : parseDate(d.closeDate),
            open : d.openPrice,
            high : d.high,
            low : d.low,
            close : d.closePrice,
            volume : d.volume
        }
    }).sort(function(a, b) { return d3.ascending(accessor.d(a), accessor.d(b)); });


    x.domain(data.map(accessor.d));
    y.domain(techan.scale.plot.ohlc(data, accessor).domain());

    svg.append("g")
            .datum(data)
            .attr("class", "close")
            .call(close);

    svg.append("g")
            .attr("class", "x axis")
            .attr("transform", "translate(0," + height + ")")
            .call(xAxis);

    svg.append("g")
            .attr("class", "y axis")
            .call(yAxis)
            .append("text")
            .attr("transform", "rotate(-90)")
            .attr("y", 6)
            .attr("dy", ".71em")
            .style("text-anchor", "end")
            .text("Price ($)");
});

score 1 · Accepted Answer · answered Jul 06 '16 at 11:24

1

I you can stock your data in a json file, you have just to use the function

d3.json("file.json",callback);

after, you have to change the name of the attributes in the code (the attirbutes on his csv are probably differents to your attributes in json)

callback, is usually a function but i don't think you have any other change to do in your code.

Verify your json (use a website like http://jsonprettyprint.com/), test the code on your computer (http://bl.ocks.org/andredumas/af8674d57980790137a0) with the default csv to see if it's work. It it's work, change to use json (like i told you).

answered Jul 06 '16 at 11:24

Florian Bury

91
8

Thanks Florian, please see updated code. Not sure how to construct the callback. My attribute names are looking ok, I can print the values to console during the forEach loop ok – Jul 07 '16 at 09:59
1

I think your error is in the foreEach. In front aff all your numeric values, you have to put a "+" like that : open : +d.openPrice But i don't understand why you don't use the map function like the code taken in sample. It's work normally with a json too. Did you tested the code just changing the attributes name and keeping the map function (instead of your foreach) ? – Florian Bury Jul 07 '16 at 11:38
Wow, it rendered :) Using map instead of forEach, thanks so much, it's been weeks on and off playing around with this! I've updated the code in the question to the working version. – Jul 07 '16 at 11:47
that's greats. Thanks for feedback. – Florian Bury Jul 07 '16 at 11:50

Using techanJS D3 examples with JSON data

1 Answers1