Draw D3 Simple Line chart With an Array

Question

I am Trying to Implement this code: http://bl.ocks.org/3883245, but instead of loading a TSV file, i am loading the data from an array. Here is how the array looks Like:

[["2012-10-02",2],["2012-10-09", 2], ["2012-10-12", 2]]

and then I applied this function on it to get CSV Format: var data = d3.csv.format(BigWordsDates2[ArrayIndex]);

but still nothing shows up.

Here is the whole code: I think I am not that far from getting it but I have been working on it for 3 days and still cant get it to work:

var margin = {top: 20, right: 20, bottom: 30, left: 50},
        width = 80 - margin.left - margin.right,
        height = 80 - margin.top - margin.bottom;

        var data = d3.csv.format(BigWordsDates2[ArrayIndex]);

        var parseDate = d3.time.format("%Y-%b-%d").parse;

        var x = d3.time.scale()
            .range([0, width]);

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

        var xAxis = d3.svg.axis()
            .scale(x)
            .orient("bottom");

        var yAxis = d3.svg.axis()
            .scale(y)
            .orient("left");

        var line = d3.svg.line()
            .x(function(d) { return x(d.date); })
            .y(function(d) { return y(d.close); });

        var svg = d3.select("#Graph").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 + ")");

        d3.csv.parseRows(data, function(data) {
          data.forEach(function(d) {
            d.date = parseDate(d.date);
            d.close = parseInt(d.close);
          });

         x.domain(d3.extent(data, function(d) { return d.date; }));
         y.domain(d3.extent(data, function(d) { return d.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 ($)");

          svg.append("path")
              .datum(data)
              .attr("class", "line")
              .attr("d", line);
        });`

I think I am also doing something wrong with the d.date and d.close but I can't figure it out either.

Answer 1

The chart uses data in the following format

[{ date: '...', close: '...'},
 { date: '...', close: '...'}]

So, you need to parse your array:

// fix your data parser
var parseDate = d3.time.format("%Y-%m-%d").parse;

var arrData = [
  ["2012-10-02",200],
  ["2012-10-09", 300], 
  ["2012-10-12", 150]];

// create a new array that follows the format
var data = arrData.map(function(d) {
    return {
      date: parseDate(d[0]),
      close: d[1]
    };
});

Here's the working version: http://jsfiddle.net/jaimem/T546B/

pd: depending on the data you might have to modify your y scale's domain.