D3 Examples - d3 interactivity example

d3 interactivity example

This line chart is constructed from a TSV file storing the daily average temperatures of New York, San Francisco and Austin over the last year. The chart employs conventional margins and a number of D3 features:

d3.tsv - load and parse data

d3.time.format - parse dates

d3.time.scale - x-position encoding

d3.scale.linear - y-position encoding

d3.scale.category10, a d3.scale.ordinal - color encoding

d3.extent, d3.min and d3.max - compute domains

d3.keys - compute column names

d3.svg.axis - display axes

d3.svg.line - display line shape

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<!DOCTYPE html>
<meta charset="utf-8">
<link rel="stylesheet" type="text/css" href="st.css">
<svg width="960" height="500"></svg>
<script src="//d3js.org/d3.v4.min.js"></script>
<script>
​
var svg = d3.select("svg"),
    margin = {top: 20, right: 80, bottom: 30, left: 50},
    width = svg.attr("width") - margin.left - margin.right,
    height = svg.attr("height") - margin.top - margin.bottom;
svg.call(d3.zoom().on("zoom", function () {
    svg.attr("transform", d3.event.transform)
 }));
 var g = svg.append("g").attr("transform", "translate(" + margin.left + "," + margin.top + ")");
​
var focusOne = d => d3.selectAll('.line').style('stroke', function(title){return (d.id!==title.id && !d3.select(".line[cname='"+d.id+"']").classed('invis'))?'grey':z(title.id);});
var focusAll = d => d3.selectAll('.line').style('stroke', function(title, i){return z(title.id);});
  
var parseTime = d3.timeParse("%Y%m%d");
​
var x = d3.scaleTime().range([0, width]),
    y = d3.scaleLinear().range([height, 0]),
    z = d3.scaleOrdinal(d3.schemeCategory10);
​
  var voronoi = d3.voronoi()
    .x(function(d) { return x(d.date); })
    .y(function(d) { return y(d.temperature); })
    .extent([[-margin.left, -margin.top], [width + margin.right, height + margin.bottom]]);
  
var line = d3.line()
    .curve(d3.curveBasis)
    .x(function(d) { return x(d.date); })
    .y(function(d) { return y(d.temperature); });
​
d3.tsv("data.tsv", type, function(error, data) {
  if (error) throw error;
​
  var cities = data.columns.slice(1).map(function(id) {
    return {
      id: id,
      values: data.map(function(d) {
        return {date: d.date, temperature: d[id]};
      })
    };
  });
​
  x.domain(d3.extent(data, function(d) { return d.date; }));
​
  y.domain([
    d3.min(cities, function(c) { return d3.min(c.values, function(d) { return d.temperature; }); }),
    d3.max(cities, function(c) { return d3.max(c.values, function(d) { return d.temperature; }); })
  ]);
​
  z.domain(cities.map(function(c) { return c.id; }));
​
  g.append("g")
      .attr("class", "axis axis--x")
      .attr("transform", "translate(0," + height + ")")
      .call(d3.axisBottom(x));
​
  g.append("g")
      .attr("class", "axis axis--y")
      .call(d3.axisLeft(y))
    .append("text")
      .attr("transform", "rotate(-90)")
      .attr("y", 6)
      .attr("dy", "0.71em")
      .attr("fill", "#000")
      .text("Temperature, ºF");
​
  var city = g.selectAll(".city")
    .data(cities)
    .enter().append("g")
      .attr("class", "city");
​
  city.append("path")
      .attr("class", "line")
      .attr('cname', function(d){return d.id;})
      .attr("d", function(d) { return line(d.values); })
      .style("stroke", function(d) { return z(d.id); });
​
  city.append("text")
      .datum(function(d) { return {id: d.id, value: d.values[d.values.length - 1]}; })
      .attr("transform", function(d) { return "translate(" + x(d.value.date) + "," + y(d.value.temperature) + ")"; })
      .attr("x", 3)
      .attr("dy", "0.35em")
            .attr('class', 'citytext')
      .style("font", "10px sans-serif")
        .on('mouseover', focusOne)
        .on('mouseout', focusAll)
        .on('click', function(d){
    console.log('click')
                            d3.selectAll('.line')
                  .classed('invis', function(ld){
                    return ld.id===d.id?!d3.select(this).classed('invis'):d3.select(this).classed('invis');
                    })
         })
    .text(function(d) { return d.id; });
  
  
  
  //voronia
  var focus = g.append("g")
      .attr("transform", "translate(-100,-100)")
      .attr("class", "focus");
​
  focus.append("circle")
      .attr("r", 3.5);
​
  focus.append("text")
      .attr("y", -10);
​
  var voronoiGroup = g.append("g")
      .attr("class", "voronoi");
​
});
​
function type(d, _, columns) {
  d.date = parseTime(d.date);
  for (var i = 1, n = columns.length, c; i < n; ++i) d[c = columns[i]] = +d[c];
  return d;
}
​
</script>
​
    