Add VT2-examples: all 6 chapters of 'Visualize This' (110 files) — data scraping, ETL, trends, categorical, multivariate, spatial, distribution analysis

VT2-examples/vt2-ch6-codedata-dir/web/differencechart/js/differencechart.js

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+// Dimensions of chart.
+let margin = { top: 30, right: 10, bottom: 30, left: 45 },
+    // width = parseInt(d3.select('#chart').style('width'), 10) - margin.left - margin.right,
+    width = 600 - margin.left - margin.right,
+    height = width*.8 - margin.top - margin.bottom;
+    
+let svg = d3.select("#chart").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 + ")");
+    
+    
+// Scales: x and y
+let x = d3.scaleLinear()
+    .domain([1909, 2017])
+	.range([0, width]);
+let y = d3.scaleLinear()
+    .domain([0, 100])
+	.range([height, 0]);
+    
+
+// Geometries
+let area = d3.area()
+    .x(d => x(d.year))
+    .y1(d => y(d.amt));
+let line = d3.line()
+    .x(d => x(d.year))
+    .y(d => y(d.amt));
+    
+
+let xAxis, yAxis, xAxisEl, yAxisEL;
+
+let meats, beef, chicken;
+
+    
+// Load data
+const meatData = Promise.all([
+    d3.csv("data/beef-vs-chicken-difference.csv", d3.autoType)
+]);
+meatData.then(function(data) {
+    
+    meats = data[0];
+    console.log(meats);
+    
+    svg.datum(meats);
+    
+    // Initialize chart now that data is loaded.
+    initChart();
+});
+
+
+
+function initChart() {
+    
+    // x-axis
+    xAxis = d3.axisBottom(x)
+        .ticks(4)
+        .tickFormat(d => d)
+	    .tickSize(-height-8)
+	    .tickPadding(5);
+    xAxisEl = svg.append("g")
+	    .attr("class", "x axis bottom")
+	    .attr("transform", "translate(0,"+(height+8)+")");
+    xAxisEl.call(xAxis);
+
+    // y-axis
+    yAxis = d3.axisLeft(y)
+        // .ticks(7)
+        .ticks(5)
+	    .tickSize(-width-8)
+	    .tickPadding(5);
+    yAxisEl = svg.append("g")
+	    .attr("class", "y axis left")
+        .attr("transform", "translate("+(-8)+",0)");
+    yAxisEl.append("text")
+	    .attr("class", "axistitle")
+	    .attr("x", 0).attr("y", 0)
+        .attr("dx", "-2.25em")
+        .attr("dy", "-1.5em")
+        .style("text-anchor", "start")
+        .text("Pounds per capita");
+    yAxisEl.call(yAxis);
+    
+    // Area clipping paths
+    svg.append("clipPath")
+        .attr("id", "clip-above")
+      .append("path")
+        .attr("d", d3.area()
+            .x(d => x(d.Year))
+            .y0(0)
+            .y1(d => y(d.Chicken)));
+    svg.append("clipPath")
+        .attr("id", "clip-below")
+        .append("path")
+        .attr("d", d3.area()
+            .x(d => x(d.Year))
+            .y0(height)
+            .y1(d => y(d.Chicken)));
+
+    // Area differences
+    svg.append("path")
+        .attr("class", "area above")
+        .attr("clip-path", "url(#clip-above)")
+        .attr("fill", "#fdad94")
+        .attr("d", d3.area()
+            .x(d => x(d.Year)).y0(height).y1(d => y(d.Beef)));
+    svg.append("path")
+        .attr("class", "area below")
+        .attr("fill", "#f9e59f")
+        .attr("clip-path", "url(#clip-below)")
+        .attr("d", d3.area()
+            .x(d => x(d.Year)).y0(0).y1(d => y(d.Beef)));
+
+    // Lines
+    svg.append("path")
+        .attr("class", "line chicken")
+        .attr("fill", "none")
+        .attr("stroke", "#bf980d")
+        .attr("stroke-width", "2px")
+        .attr("d", d3.line()
+            .x(d => x(d.Year))
+            .y(d => y(d.Chicken)));
+    svg.append("path")
+        .attr("class", "line beef")
+        .attr("fill", "none")
+        .attr("stroke", "#fb470e")
+        .attr("stroke-width", "2px")
+        .attr("d", d3.line()
+            .x(d => x(d.Year))
+            .y(d => y(d.Beef)));
+    
+    
+    setAnnotation();
+}
+
+
+
+
+function setAnnotation() {
+    svg.append("text")
+        .attr("class", "mainlab")
+        .attr("fill", "#fb470e")
+        .attr("x", x(1962))
+        .attr("y", y(40))
+        .text("BEEF");
+    
+    svg.append("text")
+        .attr("text-anchor", "end")
+        .attr("class", "mainlab")
+        .attr("fill", "#bf980d")
+        .attr("x", x(2017))
+        .attr("y", y(65))
+        .text("CHICKEN");
+}
+