I'm trying to create a sankey chart using the d3 sankey plugin with dynamic shipping data. It works great most of the time except when I get a data set like this:
[{"DeparturePort":"CHARLESTON","ArrivalPort":"BREMERHAVEN","volume":5625.74},{"DeparturePort":"CHARLESTON","ArrivalPort":"ITAPOA","volume":2340},{"DeparturePort":"PT EVERGLADES","ArrivalPort":"PT AU PRINCE","volume":41.02},{"DeparturePort":"BREMERHAVEN","ArrivalPort":"CHARLESTON","volume":28}]
The key to my issue is the first and last entry in the data set. It seems that having opposite directions in the same sankey chart sends the javascript into an infinite loop and kills the browser. Any ideas on how to prevent this from happening?
Here's my chart code where raw would be the object above:
var data = raw;
var units = "Volume";
var margin = { top: 100, right: 0, bottom: 30, left: 0 },
width = $("#"+divID).width() - margin.left - margin.right,
height = divID == "enlargeChart" ? 800 - margin.top - margin.bottom : 600 - margin.top - margin.bottom;
var formatNumber = d3.format(",.0f"), // zero decimal places
format = function (d) { return ""; },
color = d3.scale.ordinal()
.range(["#0077c0", "#FF6600"]);
// append the svg canvas to the page
var svg = d3.select("#"+divID).append("svg")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.style("font-size", "12px")
.append("g")
.attr("transform",
"translate(" + margin.left + "," + margin.top + ")");
// Set the sankey diagram properties
var sankey = d3.sankey(width)
.nodeWidth(10)
.nodePadding(10)
.size([width, height]);
var path = sankey.link();
// load the data (using the timelyportfolio csv method)
//d3.csv("sankey.csv", function (error, data) {
//set up graph in same style as original example but empty
graph = { "nodes": [], "links": [] };
var checklist = [];
data.forEach(function (d) {
if ($.inArray(d.DeparturePort, checklist) == -1) {
checklist.push(d.DeparturePort)
graph.nodes.push({ "name": d.DeparturePort });
}
if ($.inArray(d.ArrivalPort, checklist) == -1) {
checklist.push(d.ArrivalPort)
graph.nodes.push({ "name": d.ArrivalPort });
}
graph.links.push({
"source": d.DeparturePort,
"target": d.ArrivalPort,
"value": +d.volume
});
});
// return only the distinct / unique nodes
graph.nodes = d3.keys(d3.nest()
.key(function (d) { return d.name; })
.map(graph.nodes));
// loop through each link replacing the text with its index from node
graph.links.forEach(function (d, i) {
graph.links[i].source = graph.nodes.indexOf(graph.links[i].source);
graph.links[i].target = graph.nodes.indexOf(graph.links[i].target);
});
//now loop through each nodes to make nodes an array of objects
// rather than an array of strings
graph.nodes.forEach(function (d, i) {
graph.nodes[i] = { "name": d };
});
sankey
.nodes(graph.nodes)
.links(graph.links)
.layout(32);
// add in the links
var link = svg.append("g").selectAll(".link")
.data(graph.links)
.enter().append("path")
.attr("class", "link")
.attr("d", path)
.style("stroke-width", function (d) { return Math.max(1, d.dy); })
.sort(function (a, b) { setTimeout(function () { return b.dy - a.dy; }, 10);});
// add the link titles
link.append("title")
.text(function (d) {
return d.source.name + " → " +
d.target.name + "\n" + d.value.toFixed(0) + " TEU";
});
$("#" + divID + " .loading").addClass("hide");
// add in the nodes
var node = svg.append("g").selectAll(".node")
.data(graph.nodes)
.enter().append("g")
.attr("class", "node")
.attr("transform", function (d) {
//setTimeout(function () {
return "translate(" + d.x + "," + d.y + ")";
//}, 10);
})
.call(d3.behavior.drag()
.origin(function (d) { return d; })
.on("dragstart", function () {
this.parentNode.appendChild(this);
})
.on("drag", dragmove));
// add the rectangles for the nodes
node.append("rect")
.attr("height", function (d) { if (d.dy < 0) { d.dy = (d.dy * -1); } return d.dy; })
.attr("width", sankey.nodeWidth())
.style("fill", function (d) {
return d.color = color(d.name);
})
.style("stroke", function (d) {
return d3.rgb(d.color);
})
.append("title")
.text(function (d) {
return d.name + "\n" + format(d.value);
});
// add in the title for the nodes
node.append("text")
.attr("x", -6)
.attr("y", function (d) { return d.dy / 2; })
.attr("dy", ".35em")
.attr("text-anchor", "end")
.style("stroke", function (d) { return "#000000" })
.attr("transform", null)
.text(function (d) { return d.name; })
.filter(function (d) { return d.x < width / 2; })
.attr("x", 6 + sankey.nodeWidth())
.attr("text-anchor", "start");
// the function for moving the nodes
function dragmove(d) {
d3.select(this).attr("transform",
"translate(" + d.x + "," + (
d.y = Math.max(0, Math.min(height - d.dy, d3.event.y))
) + ")");
sankey.relayout();
link.attr("d", path);
}
}, 0)
