DV4

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>  
  <script src="https://d3js.org/queue.v1.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  
    .province:hover {
        opacity: 0.5;
    }
    .hidden {
        display: none;
    }
    div.tooltip {
        color: #222;
        background-color: #fff;
        padding: .5em;
        text-shadow: #f5f5f5 0 1px 0;
        border-radius: 2px;
        opacity: 0.9;
        position: absolute;
    }
  </style>
</head>

var svg = d3.select( "body" )
  		.append( "svg" )
		  .attr( "width", width )
		  .attr( "height", height );
    
    // French map 
    var projection = d3.geoConicConformal().center([2.454071, 46.279229]).scale(2500);
   	
    // On definie une echelle de couleur
		var color = d3.scaleQuantize()  
    			.range(["rgb(213,239,204)", 
                  "rgb(169,221,160)", 
                  "rgb(94,186,97)", 
                  "rgb(42,141,71)", 
                  "rgb(0,91,36)"]);
    
    var tooltip = d3.select('body')
    								.append('div')
    								.attr('class', 'hidden tooltip');
           
    var path = d3.geoPath() // d3.geo.path avec d3 version 3
                 .projection(projection);

d3.csv("GrippeFrance2014.csv", function(data) {
      	 var france;
      	 var listWeeks = Object.keys(data[0]);

d3.json("regions.json", function(json) {
        		// first value for slider
            var first = listWeeks[1];
            d3.select('#week').html(first);
            // update the week in slider
            d3.select("#slider").on("input", function() {
              updateViz(+this.value);
            });
          
        //On fusionne les donnees avec le GeoJSON des regions
      	for (var i = 0; i < data.length; i++) {
          // Find the name of the region in csv file
          var dataState = data[i].region;
        	for (var j = 0; j< json.features.length; j++){
            var jsonState = json.features[j].properties.nom;
            if (dataState == jsonState) {
           	  json.features[j].properties.tab =  Object.values(data[i]);
             	//stop because result found
               break;
            }
          }
        }
 
        svg.selectAll("path")
          .data(json.features)
          .enter()
          .append("path")
          .attr("d", path);
        
        france = json; 
        drawMap(1); 
        }); // End of "d3.json("regions.json", function(json){"
      
      //update elements 
    	function updateViz(val){
      	d3.select('#week').html(listWeeks[val]);
      	drawMap(val); 
    	};
      
      // Draw the map
      function drawMap(currentWeek){
        var nbr;
        //Set input domain for color scale
      	color.domain([
            d3.min(data, function(x) { return parseFloat(Object.values(x)[currentWeek]);}), 
            d3.max(data, function(x) { return parseFloat(Object.values(x)[currentWeek]);})
          ]);
      
        carte = svg.selectAll("path")
           .data(france.features);
        carte
          .on('mousemove', function(d) {
    					if(d.properties.tab == undefined){
           				nbr = "undefined";
        			}else { 
             		  nbr = d.properties.tab[currentWeek]; 
              	}
          		var mouse = d3.mouse(svg.node()).map(function(d) {
                 return parseInt(d);
              });
          
              tooltip.classed('hidden', false)
                     .attr('style', 'left:' + (mouse[0] + 15) +
                             'px; top:' + (mouse[1] - 35) + 'px')
                     .html(d.properties.nom + ":" + parseFloat(nbr));
                      
              })
         	.on('mouseout', function() {
              tooltip.classed('hidden', true);
              });
        
        //code in case of update of the map / change of week 
       	carte 
         .attr('class', function(d) {
                return 'province ' + d.properties.code;
             })
                .attr('d', path)
        	.style("fill", function(d) {
                // get value found above
                var tab = d.properties.tab;
                if (tab) {
                    return color(tab[currentWeek]);
                } else { 
                   	// if no value then color with Grey
                    return "#ccc";
                }
            });
        
        // fist time of coloring the map
        carte.selectAll("path")
            .enter()
            .data(france.features)
            .append("path")
            .attr("class", "enter")
            .attr("d", path)
            .style("fill", function(d) {
                  // get value found above
                  var tab = d.properties.tab;
                  if (tab) {  
                      return color(tab[currentWeek]);
                  } else { 
                      // if no value then color with Grey 
                      return "#ccc";
                  }
              });
      }; 
    });

</script>
</body>

https://d3js.org/d3.v4.min.js

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