D3 Examples - IRIS scatterplot and regression

xxxxxxxxxx
 
​
<!DOCTYPE html>
<meta charset="utf-8">
<style>
​
body {
  font: 10px sans-serif;
}
​
.tooltip {
    position: absolute;
    width: 0px;
    height: 28px;
    pointer-events: none;
}
  
.line {
    stroke: #e53100;
    fill: none;
    stroke-width: 3;
}  
​
​
​
</style>
<body>
    <script src="https://d3js.org/d3.v4.min.js"></script>
    <script>
​
var margin = {top: 20, right: 20, bottom: 30, left: 40},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;
​
var x = d3.scaleLinear()
    .range([0, width]);
​
var y = d3.scaleLinear()
    .range([height, 0]);
​
var r = d3.scaleSqrt()
        .range([3,10]);
  
var xAxis = d3.axisBottom()
        .scale(x);
​
var yAxis = d3.axisLeft()
        .scale(y);
  
var color = d3.scaleOrdinal(d3.schemeCategory10);
    
​
var symbol = d3.symbol(["circle", "cross", "diamond"]);
    
   
​
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 + ")");
​
  var tooltip = d3.select("body").append("div")
                    .attr("class", "tooltip")
                    .style("opacity", 0);
​
d3.csv('https://raw.githubusercontent.com/LyonDataViz/MOS5.5-Dataviz/master/data/iris.csv', function(error, data){
    data.forEach(function(d){
    d.petal_length = +d.petal_length;
    d.petal_width  = +d.petal_width;
    });
​
    x.domain(d3.extent(data, function(d){
        return d.petal_length;
    }));
​
    y.domain(d3.extent(data, function(d){
        return d.petal_width;
    }));
​
    r.domain(d3.extent(data, function(d){
        return d.sepal_length;
    }))();
  
  var path = svg.selectAll("path")
                .data(data)
                .enter()
                .append("path")
  
  path.attr("transform", function(d) { return "translate(" + x(d.petal_length) + ", " + y(d.petal_width) + ")"; })
                .attr("d", d3.symbol()
                                .type(function(d){
                                    if (d.species == 'setosa'){
                                        return d3.symbolSquare;
                                    }
                                    else if (d.species == 'versicolor') {
                                        return d3.symbolDiamond;
                                    }
                                    else if (d.species == 'virginica') {
                                        return d3.symbolStar;
                                    }
                                    
                                }))
                .style("fill", function(d){ return color(d.species); })
​
  svg.append('g')
    .attr('transform', 'translate(0,' + height + ')')
    .attr('class', 'x axis')
    .call(xAxis);
​
  svg.append('g')
    .attr('transform', 'translate(0,0)')
    .attr('class', 'y axis')
    .call(yAxis);
​
    svg.append('text')
        .attr('x', 10)
        .attr('y', 10)
        .attr('class', 'label')
        .text('petal Width');
​
    svg.append('text')
        .attr('x', width)
        .attr('y', height - 10)
        .attr('text-anchor', 'end')
        .attr('class', 'label')
        .text('Petal Length');
​
  svg.selectAll(".dot")
    .data(data)
  .enter().append("circle")
    .attr("class", "dot")
    .attr("r", function(d) { return r(d.petal_length); })
    .attr("cx", function(d) { return x(d.petal_length); })
    .attr("cy", function(d) { return y(d.petal_width); })
    .style("fill", function(d) { return color(d.species); })
    .on("mouseover", function(d){
           tooltip.transition()
            .duration(0)
            .style("opacity", .9);
           tooltip.html("Species:" + d.species)
            .style("left", (d3.event.pageX + 5) + "px")
            .style("top", (d3.event.pageY - 28) + "px");
         })
        .on("mouseout", function(d){
            tooltip.transition()
                .duration(500)
                .style("opacity",0);
        });
  
            // Regression lineaire
​
            var x_mean = d3.mean(data, function(d){ return d.petal_length; });
            var y_mean = d3.mean(data, function(d){ return d.petal_width; });
​
            // Coeff
            
            var xr = 0;
            var yr = 0;
            var term1 = 0;
            var term2 = 0;
            for (var i=0; i< data.length; i++){
                xr = parseFloat(data[i].petal_length) - x_mean;
                yr = parseFloat(data[i].petal_width) - y_mean;
                term1 += xr * yr;
                term2 += xr * xr;
                }
​
            var b1 = term1 / term2;
            var b0 = y_mean - (b1 * x_mean);
​
            for (i=0; i< data.length; i++){
                data[i].lin_reg_term = b0 + (data[i].petal_length * b1); 
                }
​
​
            var line = d3.line()
                .x(function(d){ return x(d.petal_length); })
                .y(function(d){ return y(d.lin_reg_term); });
​
            svg.append("path")
                .datum(data)
                .attr("class", "line")
                .attr("d", line);
​
 
    var clicked;
  
  var legend = svg.selectAll(".legend")
    .data(color.domain())
  .enter().append("g")
    .attr("class", "legend")
    .attr("transform", function(d, i) { return "translate(75," + i * 20+ ")"})
  .on("click", function(d){
    
​
        d3.selectAll(".symbol").style("opacity", 1)
      if (clicked !==d){
        d3.selectAll(".symbol")
            .filter(function (e){
          return e.species !==d
        })
        .style ("opacity", 0.1)
        clicked =d
     
      }
    else {clicked=null;}
        
    
  }); 
    
​
  legend.append("rect")
      .attr("x", 80)
      .attr("width", 18)
      .attr("height", 18)
        .style("stroke", "#000")
      .style("fill", color);
​
  legend.append("text")
      .attr("x", 75)
      .attr("y", 9)
      .attr("dy", ".35em")
      .style("text-anchor", "end")
      .text(function(d) { return d; });
  
  
  
  var rectangle = svg.append("rect")
      .attr("x", 70)
      .attr("y", 0)
        .attr("width", 110)
        .attr("height", 60)
            .style("stroke", "#000")
      .style("fill", "none");
                        
​
​
});
  
​
​
    
    
    
 </script>
​
​
    