Real time charts with D3.js

Question

I am totally new to D3.js. I am trying to create a simple sparkline with time on the X axis and numbers upto 1000 on the Y axis. I have a web socket server which pushes random numbers unto 1000 to clients. I would like to plot a graph with these values on Y axis and time (in 24 hrs format) on the X axis. I tried a few things, but none of them work properly. My graph turns out vertical and is displayed only sometimes.

Appreciate any help in getting this working.

Below is what I have in my code, which is a tweaked version of an example I found online.

data[] is populated from the web socket call.

var margin = {top: 20, right: 20, bottom: 20, left: 40},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

var x = d3.scale.linear()
    .domain([0, data[data.length -1]])
    .range([0, width]);

var y = d3.scale.linear()
    .domain([0, 100])
    .range([height, 0]);

var line = d3.svg.line()
    .x(function(d, i) { 
        var dt = new Date();
        var time = dt.getHours() + ":" + dt.getMinutes() + ":" + dt.getSeconds();
        return dt.getSeconds();
        })
    .y(function(d, i) { console.log("D is " + d+ "Y is " + y(d));return y(d); });

var svg = d3.select("body").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

svg.append("defs").append("clipPath")
    .attr("id", "clip")
  .append("rect")
    .attr("width", width)
    .attr("height", height);

svg.append("g")
    .attr("class", "x axis")
    .attr("transform", "translate(0," + y(0) + ")")
    .call(d3.svg.axis().scale(x).orient("bottom"));

svg.append("g")
    .attr("class", "y axis")
    .attr("transform", "translate(0," + x(0)+")")
    .call(d3.svg.axis().scale(y).orient("left"));

var path = svg.append("g")
    .attr("clip-path", "url(#clip)")
  .append("path")
    .datum(data)
    .attr("class", "line")
    .attr("d", line);

redraw();

function redraw() {


  path
      .attr("d", line)
      .attr("transform", null)
    .transition()
      .duration(500)
      .ease("linear")
      .attr("transform", "translate(" + x(-1) + ",0)")
      .each("end", tick);

  data.shift();

}

Could someone point me to a beginner's tutorial to D3 which will help me get started with creating different types of graphs?

Answer 1

It may help to have the structure of data you are using.

If you want to go for Angular+D3js there are a few libraries out ther that will help you get the job done quickly.

An simple library is: http://angularjs-nvd3-directives.github.io/angularjs-nvd3-directives/

Another good set of directives which use D3.js is http://krispo.github.io/angular-nvd3/#/ The Home page has a lot of examples you can check. Although it lacks of documentation, every example has a plunker and you can check how it works.