I am new to d3.js. Trying to understand the cartogram example give in http://prag.ma/code/d3-cartogram/ . Here they gave example for USA map. I am trying the same for World Map to see how things works. My cartogram map has lines in between. My data has values for only few countries so I am setting the rest of the country's value as low or 0.
<!DOCTYPE html>
<html>
<head>
<title>Cartograms with d3 & TopoJSON</title>
<meta charset="utf-8">
<meta property="og:image" content="placeholder.png">
<script src="http://d3js.org/d3.v3.min.js"></script>
<script src="lib/colorbrewer.js"></script>
<script src="lib/topojson.js"></script>
<script src="cartogram.js"></script>
<style type="text/css">
body {
font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
font-size: 14px;
line-height: 1.4em;
padding: 0;
margin: 0;
}
#container {
width: 960px;
margin: 20px auto;
}
h1 {
font-size: 200%;
margin: 0 0 15px 0;
}
h2 {
font-size: 160%;
margin: 0 0 10px 0;
}
p {
margin: 0 0 10px;
}
form, form > * {
margin: 0;
}
#status {
color: #999;
}
#map-container {
height: 700px;
text-align: center;
position: relative;
margin: 20px 0;
}
#map {
display: block;
position: absolute;
background: #fff;
width: 100%;
height: 100%;
margin: 0;
}
path.state {
stroke: #666;
stroke-width: .5;
}
path.state:hover {
stroke: #000;
}
form {
font-size: 120%;
}
select {
font-size: inherit;
}
#placeholder {
position: absolute;
z-index: -1;
display: block;
left: 0;
top: 0;
}
</style>
</head>
<body>
<div id="container">
<h1>Cartograms with d3 & TopoJSON</h1>
<form>
<p>
<label>Scale by <select id="field"></select></label>
<span id="status"></span>
</p>
</form>
<div id="map-container">
<svg id="map"></svg>
</div>
</div>
<script>
var margin = 1,
width = 970 - margin,
height = 700 - margin;
if (!document.createElementNS) {
document.getElementsByTagName("form")[0].style.display = "none";
}
var percent = (function() {
var fmt = d3.format(".2f");
return function(n) { return fmt(n) + "%"; };
})(),
fields = [
{name: "(no scale)", id: "none"},
{name: "Internet_Users", id: "internet", key: "Internet_Users", format : percent},
{name: "GDP", id: "gdp", key: "GDP"},
{name: "Literacy_rates", id: "literacy", key: "Literacy_rates", format : percent},
{name: "female_male", id: "fm", key: "female_male"},
{name: "Population", id: "pop", key: "Population"},
],
fieldsById = d3.nest()
.key(function(d) { return d.id; })
.rollup(function(d) { return d[0]; })
.map(fields),
field = fields[0],
colors = colorbrewer.RdYlBu[3]
.reverse()
.map(function(rgb) { return d3.hsl(rgb); });
var body = d3.select("body"),
stat = d3.select("#status");
var fieldSelect = d3.select("#field")
.on("change", function(e) {
field = fields[this.selectedIndex];
location.hash = "#" + [field.id]
});
fieldSelect.selectAll("option")
.data(fields)
.enter()
.append("option")
.attr("value", function(d) { return d.id; })
.text(function(d) { return d.name; });
var map = d3.select("#map").attr("width", width + margin)
.attr("height", height + margin),
zoom = d3.behavior.zoom()
.translate([-38, 32])
.scale(.95)
.scaleExtent([0.5, 10.0])
.on("zoom", updateZoom),
layer = map.append("g")
.attr("id", "layer"),
states = layer.append("g")
.attr("id", "states")
.selectAll("path");
updateZoom();
function updateZoom() {
var scale = zoom.scale();
layer.attr("transform",
"translate(" + zoom.translate() + ") " +
"scale(" + [scale, scale] + ")");
}
var proj = d3.geo.mercator().scale(145).translate([width / 2, height / 1.5]),
topology,
geometries,
rawData,
dataById = {},
carto = d3.cartogram()
.projection(proj)
.properties(function(d) {
return dataById[d.id];
})
.value(function(d) {
return +d.properties[field];
});
window.onhashchange = function() {
parseHash();
};
d3.json("data/world_countries_topo.json", function(topo) {
topology = topo;
// console.log("T",topology)
geometries = topology.objects.countries.geometries;
d3.csv("data/parallel_score.csv", function(data) {
rawData = data;
dataById = d3.nest()
.key(function(d) { return d.Id; })
.rollup(function(d) { return d[0]; })
.map(data);
init();
});
});
function init() {
var features = carto.features(topology, geometries),
path = d3.geo.path()
.projection(proj);
states = states.data(features)
.enter()
.append("path")
.attr("class", "state")
.attr("id", function(d) {
return d.Id;
})
.attr("fill", "#000")
.attr("d", path);
states.append("title");
parseHash();
}
function reset() {
stat.text("");
body.classed("updating", false);
var features = carto.features(topology, geometries),
path = d3.geo.path()
.projection(proj);
states.data(features)
.transition()
.duration(750)
.ease("linear")
.attr("fill", "#fafafa")
.attr("d", path);
states.select("title")
.text(function(d) {
return d.Id;
});
}
function update() {
var start = Date.now();
body.classed("updating", true);
var key = field.key
var fmt = (typeof field.format === "function")
? field.format
: d3.format(field.format || ","),
value = function(d) {
if(d.properties == undefined){}
else {
return +d.properties[key];
}
},
values = states.data()
.map(value)
.filter(function(n) {
return !isNaN(n);
})
.sort(d3.ascending),
lo = values[0],
hi = values[values.length - 1];
console.log("L",lo)
console.log("H",hi)
var color = d3.scale.linear()
.range(colors)
.domain(lo < 0
? [lo, 0, hi]
: [lo, d3.mean(values), hi]);
// normalize the scale to positive numbers
var scale = d3.scale.linear()
.domain([lo, hi])
.range([1, 1000]);
// tell the cartogram to use the scaled values
carto.value(function(d) {
if( value(d) == undefined) {
return lo
}
else {
console.log("SCale", (value(d)))
return scale(value(d));
}
});
// generate the new features, pre-projected
var features = carto(topology, geometries).features;
// update the data
states.data(features)
.select("title")
/*.text(function(d) {
return [d.properties.Id, fmt(value(d))].join(": ");
});*/
states.transition()
.duration(750)
.ease("linear")
.attr("fill", function(d) {
if(d.properties == undefined){
return color(lo)
}
else {
return color(value(d));
}
})
.attr("d", carto.path);
var delta = (Date.now() - start) / 1000;
stat.text(["calculated in", delta.toFixed(1), "seconds"].join(" "));
body.classed("updating", false);
}
var deferredUpdate = (function() {
var timeout;
return function() {
var args = arguments;
clearTimeout(timeout);
stat.text("calculating...");
return timeout = setTimeout(function() {
update.apply(null, arguments);
}, 10);
};
})();
var hashish = d3.selectAll("a.hashish")
.datum(function() {
return this.href;
});
function parseHash() {
var parts = location.hash.substr(1).split("/"),
desiredFieldId = parts[0],
field = fieldsById[desiredFieldId] || fields[0];
fieldSelect.property("selectedIndex", fields.indexOf(field));
if (field.id === "none") {
reset();
} else {
deferredUpdate();
location.replace("#" + [field.id].join("/"));
hashish.attr("href", function(href) {
return href + location.hash;
});
}
}
</script>
</body>
</html>
Here is the link of my map: My Map
Can Someone please explain me why I am getting this line.
Thanks.