Nutrient Parallel Coordinates IV

Previous Version. This version is implemented using D3 Version 4.

A visualization of the mean nutrient contents of all 8789 foods in USDA's SR28 Nutrient Database.

<!DOCTYPE html>
<meta charset="utf-8">
<title>Nutrient Parallel Coordinates IV</title>
<body>
<script src="https://d3js.org/d3.v4.js"></script>
<script src="render-queue.js"></script>
<link rel="stylesheet" href="style.css"></link>
<script>
var margin = {top: 66, right: 110, bottom: 20, left: 188},
    width = document.body.clientWidth - margin.left - margin.right,
    height = 340 - margin.top - margin.bottom,
    innerHeight = height - 2;

var devicePixelRatio = window.devicePixelRatio || 1;

var color = d3.scaleOrdinal()
  .range(["#5DA5B3","#D58323","#DD6CA7","#54AF52","#8C92E8","#E15E5A","#725D82","#776327","#50AB84","#954D56","#AB9C27","#517C3F","#9D5130","#357468","#5E9ACF","#C47DCB","#7D9E33","#DB7F85","#BA89AD","#4C6C86","#B59248","#D8597D","#944F7E","#D67D4B","#8F86C2"]);

var xscale = d3.scalePoint()
    .domain(d3.range(dimensions.length))
    .range([0, width]);

var yAxis = d3.axisLeft();

var container = d3.select("body").append("div")
    .attr("class", "parcoords")
    .style("width", width + margin.left + margin.right + "px")
    .style("height", height + margin.top + margin.bottom + "px");

var svg = container.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 canvas = container.append("canvas")
    .attr("width", width * devicePixelRatio)
    .attr("height", height * devicePixelRatio)
    .style("width", width + "px")
    .style("height", height + "px")
    .style("margin-top", margin.top + "px")
    .style("margin-left", margin.left + "px");

var ctx = canvas.node().getContext("2d");
ctx.globalCompositeOperation = 'darken';
ctx.globalAlpha = 0.15;
ctx.lineWidth = 1.5;
ctx.scale(devicePixelRatio, devicePixelRatio);

var output = d3.select("body").append("pre");

var axes = svg.selectAll(".axis")
    .data(dimensions)
  .enter().append("g")
    .attr("class", function(d) { return "axis " + d.key.replace(/ /g, "_"); })
    .attr("transform", function(d,i) { return "translate(" + xscale(i) + ")"; });

d3.csv("nutrient.csv", function(error, data) {
  if (error) throw error;

// shuffle the data!
  data = d3.shuffle(data);
  console.log(data);

data.forEach(function(d) {
    dimensions.forEach(function(p) {
      d[p.key] = !d[p.key] ? null : p.type.coerce(d[p.key]);
    });

// truncate long text strings to fit in data table
    for (var key in d) {
      if (d[key] && d[key].length > 35) d[key] = d[key].slice(0,36);
    }
  });

// type/dimension default setting happens here
  dimensions.forEach(function(dim) {
    if (!("domain" in dim)) {
      // detect domain using dimension type's extent function
      dim.domain = d3_functor(dim.type.extent)(data.map(function(d) { return d[dim.key]; }));
    }
    if (!("scale" in dim)) {
      // use type's default scale for dimension
      dim.scale = dim.type.defaultScale.copy();
    }
    dim.scale.domain(dim.domain);
  });

var render = renderQueue(draw).rate(50);

ctx.clearRect(0,0,width,height);
  ctx.globalAlpha = d3.min([0.85/Math.pow(data.length,0.3),1]);
  render(data);

axes.append("g")
      .each(function(d) {
        var renderAxis = "axis" in d
          ? d.axis.scale(d.scale)  // custom axis
          : yAxis.scale(d.scale);  // default axis
        d3.select(this).call(renderAxis);
      })
    .append("text")
      .attr("class", "title")
      .attr("text-anchor", "start")
      .text(function(d) { return "description" in d ? d.description : d.key; });

// Add and store a brush for each axis.
  axes.append("g")
      .attr("class", "brush")
      .each(function(d) {
        d3.select(this).call(d.brush = d3.brushY()
          .extent([[-10,0], [10,height]])
          .on("start", brushstart)
          .on("brush", brush)
          .on("end", brush)
        )
      })
    .selectAll("rect")
      .attr("x", -8)
      .attr("width", 16);

d3.selectAll(".axis.food_group .tick text")
    .style("fill", color);
    
  output.text(d3.tsvFormat(data.slice(0,24)));

function project(d) {
    return dimensions.map(function(p,i) {
      // check if data element has property and contains a value
      if (
        !(p.key in d) ||
        d[p.key] === null
      ) return null;

return [xscale(i),p.scale(d[p.key])];
    });
  };

ctx.lineTo(p[0],p[1]);
    });
    ctx.stroke();
  }

function brushstart() {
    d3.event.sourceEvent.stopPropagation();
  }

// Handles a brush event, toggling the display of foreground lines.
  function brush() {
    render.invalidate();

// show ticks for active brush dimensions
    // and filter ticks to only those within brush extents
    /*
    svg.selectAll(".axis")
        .filter(function(d) {
          return actives.indexOf(d) > -1 ? true : false;
        })
        .classed("active", true)
        .each(function(dimension, i) {
          var extent = extents[i];
          d3.select(this)
            .selectAll(".tick text")
            .style("display", function(d) {
              var value = dimension.type.coerce(d);
              return dimension.type.within(value, extent, dimension) ? null : "none";
            });
        });

// reset dimensions without active brushes
    svg.selectAll(".axis")
        .filter(function(d) {
          return actives.indexOf(d) > -1 ? false : true;
        })
        .classed("active", false)
        .selectAll(".tick text")
          .style("display", null);
    */

ctx.clearRect(0,0,width,height);
    ctx.globalAlpha = d3.min([0.85/Math.pow(selected.length,0.3),1]);
    render(selected);

output.text(d3.tsvFormat(selected.slice(0,24)));
  }
});

function d3_functor(v) {
  return typeof v === "function" ? v : function() { return v; };
};
</script>

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