Chart Controls III

Forked from D3byEx.

There are more interactive with data. If there are more elements than the data, the extra elements(circles) will move up to top and dispared with zero radius.

The origin example uses linear scale to size circles, while I set it to pow scale. All the fancy is come from the timer function.

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v3.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0;font-family: Futura, Arial, sans-serif; }
    div#container{margin: 10px 20px; position: relative;}
    svg{border: 1px solid #ccc; background-color: #fff;}
    .tick line, path.domain{stroke: #555;stroke-width: 1;fill: none;}
    .xGroup path{stroke:none;}
    .tick text, .label{fill: #555;}
    select{
        position: absolute;
        left: 15px;
        top: 15px;
        height: 2em;
        border-radius: 5px;
        display: block;
        padding: 2px;
    }
    text.bigText{
        text-anchor: middle;
        font-size: 15em;
        opacity: 0.5;
        fill: none;
        stroke: #111;
        stroke-width: 1;
    }
  </style>
</head>

<body>
    <div id="container">
        <select name="region"></select>
    </div>
  
    <script>
    var margin      = {top: 85, bottom: 85, left: 85, right: 45},
        svgWidth    = 650,
        svgHeight   = 450,
        graphWidth  = svgWidth - margin.left - margin.right,
        graphHeight = svgHeight - margin.top - margin.bottom,
        circleSize  = [5, 50], // circle size span
        axisPadding = circleSize[1] / 2;

// X-axis is for life expectation: LifeExp
    // Y-axis is for birth rate: FertRate
    // The 3rd dimension is population represented with circleSize
    // The 4th dimension is time line: Year
    var xScale      = d3.scale.linear().range([0, graphWidth]).nice(),
        yScale      = d3.scale.linear().range([graphHeight, 0]).nice(),
        colors      = d3.scale.category10(),
        rScale      = d3.scale.pow().exponent(2).range(circleSize);

var xAxis = d3.svg.axis()
                .orient('bottom')
                .scale(xScale)
                .tickSize(6,0),
        yAxis = d3.svg.axis()
                .orient('left')
                .scale(yScale)
                .tickSize(6,0);

var svg = d3.select('#container')
            .append('svg')
            .attr('width', svgWidth)
            .attr('height', svgHeight);

var graphBody = svg.append('g')
            .attr('class', 'graph')
            .attr('transform', 'translate(' +
                  [margin.left, margin.top] + ')'),
        xGroup = svg.append('g')
            .attr('class', 'xGroup')
            .attr('transform', 'translate(' +
                  [margin.left,
                  margin.top + graphHeight + axisPadding] +
                  ')'),
        yGroup = svg.append('g')
            .attr('class', 'yGroup')
            .attr('transform', 'translate(' +
                  [margin.left - axisPadding,
                  margin.top] +
                  ')');
    var bigText = graphBody.append('text')
        .attr('transform', 'translate(' +
                  [graphWidth / 2,graphHeight / 2] + ')')
        .attr('class', 'bigText')
        .attr('dy', 70);

var url = 'lfp_all.csv';
    // global decleared variables
    var newData, minYear, maxYear, 
        currentYear, currentData, interval = 200;

d3.csv(url, function(error, data){
        data.map(function(d){
            d.Year        = +d.Year;
            d.LifeExp     = +d.LifeExp;
            d.FertRate    = +d.FertRate;
            d.Population  = +d.Population;
        });

// Find all the values spans for axis domains
        var LifeExtent = d3.extent(data, function(d){ return d.LifeExp; }),
            maxFertRate = d3.max(data, function(d){ return d.FertRate; }),
            PopulationExtent = d3.extent(data, function(d){ return d.Population; }),
            yearExtent = d3.extent(data, function(d){ return d.Year; }),
            regions = d3.set(data.map(function(d){ return d.Region; }))
                .values()
                .sort();

minYear = yearExtent[0];
        maxYear = yearExtent[1];
        newData = d3.nest()
                .key(function(d){return d.Year;})
                .map(data);

// add 'All' as the 1st option
        var optItems = regions.slice();
        optItems.unshift('All')
        var opts = d3.select('select[name=region]');
        opts
            .selectAll('option')
            .data(optItems)
            .enter()
            .append('option')
            .property('value', function(d,i){ return d; })
            .html(function(d,i){ return d; });
        opts.on('change', optChange)

// add axis domain
        xScale.domain([LifeExtent[0]* 0.9, LifeExtent[1]* 1.1]);
        yScale.domain([0, maxFertRate]);
        rScale.domain(PopulationExtent);
        colors.domain(regions);

// Drawing of the axises
        xGroup.call(xAxis);
        yGroup.call(yAxis);

// Drawing of labels    
        yGroup.append('text')
            .attr('transform', 
                  'translate(' +
                  [-30, graphHeight / 2] +
                  ')rotate(' + -90 + ')')
            .attr('class', 'label yLabel')
            .attr('text-anchor', 'middle')
            .text('[ FertRate ]');

xGroup.append('text')
            .attr('transform', 
                  'translate(' +
                  [graphWidth / 2, 40] +
                  ')')
            .attr('class', 'label xLabel')
            .attr('text-anchor', 'middle')
            .text('[ Life Expectation ]');

// graph drawing area, initial setting
        opts.property('value', 'All');
        currentYear = minYear;
        d3.timer(callback(), interval);
    })

// year update
        bigText.html(year);

var circles = graphBody
            .selectAll('circle')
            .attr('class', 'bubble')
            .data(data, function(d){return d.CountryName});

// update circles
        circles
            .transition()
            .each(function(d,i){
                d3.select(this).attr({
                    cx: xScale(d.LifeExp),
                    cy: yScale(d.FertRate),
                    r: rScale(d.Population),
                });
            });
        // append circles if there is More data
        circles
            .enter()
            .append('circle')
            .each(function(d,i){
                d3.select(this).attr({
                    cx            : xScale(d.LifeExp),
                    cy            : yScale(d.FertRate),
                    r             : rScale(d.Population),
                    fill          : colors(d.Region),
                    'fill-opacity': 0.5,
                    stroke        : colors(d.Region),
                    'stroke-width': 1
                });
            });

// delet circles if there is Less data
        circles
            .exit()
            .transition()
            .duration(500)
            .attr('cy', 0)
            .attr('r', 0)
            .remove();
    }

// timer callback
    var callback = function(){
        return function(){
            currentYear++;
            if(currentYear <= maxYear){
                redraw(currentYear);
                d3.timer(callback(), interval);
            };
            return true;
        };
    };

// option input change event
    function optChange(){
        graphBody.selectAll('circle').remove();
        currentYear = minYear;
        d3.timer(callback(), interval);
    }
    </script>
</body>

https://d3js.org/d3.v3.min.js