wealth and heath

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      <title>My Page Title</title>
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      <style>
         .container {
            display: inline-block;
            position: relative;
         }
         h2 {
            font-family: 'Roboto', sans-serif;
            font-size: 54px;
            margin-left: 40px;
            margin-bottom: 0px;
         }
         h1 {
            font-family: 'Roboto', sans-serif;
            font-size: 200px;
            position: absolute;
            right: 0px;
            bottom: 20px;
            margin-bottom: 0px;
            color: #ccc;
         }
      </style>
   </head>
   <body>
      <h2>The Wealth & Health of Nations</h2>
      <div class='container'>
      </div>
      <script>

var margin = {top: 40, right: 40, bottom: 40, left: 40}
         
         var width = 960 - margin.left - margin.right;
         var height = 540 - margin.top - margin.bottom;

var loadYearMinMax = function(nations) {
            var nationYears = nations.map(function(nation) {
              var incomeMinMax = d3.extent(nation.income, function(i) {return i[0]})
              var lifeMinMax = d3.extent(nation.lifeExpectancy, function(i) {return i[0]})
              var popMinMax = d3.extent(nation.population, function(i) {return i[0]})
              var allMinMax = d3.merge([incomeMinMax, lifeMinMax, popMinMax])
              return d3.extent(allMinMax)
            })
            return d3.extent(d3.merge(nationYears))
         }

// Add Year 2009 if it isn't there
         var addLastYear = function(nation, attr, years) {
            var last = nation[attr][nation[attr].length-1]
            var firstYear = years[0]
            var lastYear = years[years.length-1]
            if(nation[attr].length < years.length && last[0] != lastYear) {
               nation[attr].push([lastYear, last[1]])
            }
            return nation[attr]
         }

// Add Missing Year
         var interpolateAttr = function(nation, year, index, attr) {
            if(index === 0 && nation[attr][0][0] != year) {
               nation[attr].unshift([year, nation[attr][0][1]])
            } else if(nation[attr][index] && nation[attr][index][0] != year) {
               
               var prev = index-1;
               var next = nation[attr].length-1 == index ? index : index+1;
               if(nation[attr][prev] && nation[attr][next]) {
                  var p1 = {x: nation[attr][prev][0], y: nation[attr][prev][1]};
                  var p3 = {x: nation[attr][next][0], y: nation[attr][next][1]};
                  var p2 = {x: year};
                  var y = (((p2.x - p1.x)*(p3.y-p1.y))/(p3.x = p1.x))+p1.y;
                  nation[attr].splice(index, 0, [year, y]);
               } 
            }
            return nation[attr]
         }

var buildNewNation = function(nation, index) {
            return {
               name: nation.name,
               region: nation.region,
               income: nation.income[index][1],
               lifeExpectancy: nation.lifeExpectancy[index][1],
               population: nation.population[index][1]
            }
         }

var loadRange = function() {
            return {
               x: [0, width],
               y: [height, 0],
               radius: [1, 60],
               color: ['#45CCFF','#49E83E','#FFD432','#E80030','#B243FF','#080CFF']
            }
         }

var loadDomain = function(x, y, radius, color) {
            return {
               x: d3.extent(x),
               y: d3.extent(y),
               radius: d3.extent(radius),
               color: color
            }
         }

var loadScale = function(domain, range) {
            return {
               x: d3.scaleLog().domain(domain.x).range(range.x),
               y: d3.scaleLinear().domain(domain.y).range(range.y),
               color: d3.scaleOrdinal().domain(domain.color).range(range.color),
               radius: d3.scaleSqrt().domain(domain.radius).range(range.radius)
            }
         }

var drawAxes = function(scale, graph) {
            var xAxis = d3.axisBottom().ticks(10, d3.format("($.0f")).scale(scale.x);
            var yAxis = d3.axisLeft().scale(scale.y);
            graph.append('g')
               .attr('transform', 'translate(0,'+height+')')
               .call(xAxis)
            graph.append('g')
               .call(yAxis)
         }

var drawSvg = function() {
            var svgWidth = width + margin.left + margin.right;
            var svgHeight = height + margin.top + margin.bottom
            var graph = d3.select('.container')
               .append('svg')
                  .attr('width', svgWidth)
                  .attr('height', svgHeight)
               .append('g')
                  .attr('transform', 'translate('+margin.left+','+margin.top+')')
            d3.select('.container').append('h1')
            return graph
         }

var draw = function(graph, nations, scale) {
            if(currentYear > 2009) {
               return clearInterval(interval)
            } else {
               d3.select('h1').text(currentYear)
               var t = d3.transition().duration(300);
               var oldCircles = graph.selectAll('circle')
                  .data(nations, function(nation) {return nation.name})

if(currentYear === 1800 || currentYear === 2000) {
                  console.log(oldCircles)
               }
               
               oldCircles.exit().remove();

var newCircles = oldCircles.enter()
                  .append('circle')
                     .attr('cx', function(nation) {return scale.x(nation.income)})
                     .attr('cy', function(nation) {return scale.y(nation.lifeExpectancy)})

var circles = newCircles.merge(oldCircles)
                  .transition(t)
                  .attr('cx', function(nation) {return scale.x(nation.income)})
                  .attr('cy', function(nation) {return scale.y(nation.lifeExpectancy)})
                  .attr('r', function(nation) {return scale.radius(nation.population)})
                  .attr('fill', function(nation) {return scale.color(nation.region)})
                  .attr('fill-opacity', '0.5')
                  .attr('stroke-width', '1px')
                  .attr('stroke', function(nation) {return scale.color(nation.region)})
            }
            currentYear++
         }

var startInterval = function(graph, nations, scale) {
            return window.setInterval(function() {
              draw(graph, nations[currentYear], scale)
            }, 100);
         }

var interval;
         var currentYear = 1800

d3.json('nations.json', function(error, nations) {
            var yearMinMax = loadYearMinMax(nations)
            var regions = d3.nest().key(function(n) {
                  return n.region
               }).entries(nations).map(function(r) {
                  return r.key
               })
            var years = []
            var incomes = []
            var populations = []
            var lifeExpectancies = []
            var newNations = {}
            for(var year=yearMinMax[0]; year<=yearMinMax[1]; ++year) {
               years.push(year)
               newNations[year] = []
            }
            nations.forEach(function(nation) {
               nation.income = addLastYear(nation, 'income', years)
               nation.lifeExpectancy = addLastYear(nation, 'lifeExpectancy', years)
               nation.population = addLastYear(nation, 'population', years)
               years.forEach(function(year, index) {
                  nation.income = interpolateAttr(nation, year, index,'income')
                  nation.lifeExpectancy = interpolateAttr(nation, year, index,'lifeExpectancy')
                  nation.population = interpolateAttr(nation, year, index,'population')
                  var newNation = buildNewNation(nation, index)
                  incomes.push(newNation.income)
                  populations.push(newNation.population)
                  lifeExpectancies.push(newNation.lifeExpectancy)
                  newNations[year].push(newNation)
               })
            })
            var domain = loadDomain(incomes, lifeExpectancies, populations, regions)
            var range = loadRange()
            var scale = loadScale(domain, range)

var graph = drawSvg()
            drawAxes(scale, graph)
            interval = startInterval(graph, newNations, scale)
         })
      </script>
   </body>
</html>

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