How to center d3.js map after changing projection on the fly? - javascript

I am trying to create a map where the user can select a new projection and it'll be applied on the fly.
here is what I did (you can find a demo here)
<!DOCTYPE html>
<html>
<head>
<meta content="utf-8">
<style type="text/css">
svg {
border: 1px solid #ccc;
}
path {
fill: #ccc;
stroke: #fff;
stroke-width: .5px;
}
path:hover {
fill: #00AEEC;
}
#projectionList {
width: 200px;
height: 500px;
float: left;
border: 1px solid grey;
}
</style>
</head>
<body>
<div id="mainContainer">
<div id="projectionList">
</div>
<div id="graphContainer">
</div>
</div>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script src="http://d3js.org/topojson.v1.min.js"></script>
<script type="text/javascript">
// d3.js graph
var width = 900,
height = 500;
var path = d3.geo.path();
var svg = d3.select("#graphContainer").append("svg")
.attr("width", width)
.attr("height", height);
d3.json("tunisia.json", function(error, topology) {
console.log(topology);
//console.clear();
var featureCollection = topojson.feature(topology, topology.objects.governorates);
var bounds = d3.geo.bounds(featureCollection);
var centerX = d3.sum(bounds, function(d) {return d[0];}) / 2,
centerY = d3.sum(bounds, function(d) {return d[1];}) / 2;
var projection = d3.geo.mercator()
.scale(3000)
.center([centerX, centerY]);
path.projection(projection);
svg.selectAll("path")
.data(featureCollection.features)
.enter().append("path")
.attr("d", path);
});
//end of d3.js graph
var selectProjection = {projection_list: []};
// add the list of supported projection
/*schema of objects:
{
id: "unique_int",
projection_name: "a name",
projection_function: "a function name",
projection_description: "a description"
}
*/
//add first projection
selectProjection.projection_list.push({
id: 1,
projection_name: "azimuthalEqualArea", // to be updated with a more descriptive name
projection_function: "azimuthalEqualArea",
projection_description: "azimuthalEqualArea" // to be updated with more detailed description
});
// add second projection
selectProjection.projection_list.push({
id: 2,
projection_name: "conicConformal", // to be updated with a more descriptive name
projection_function: "conicConformal",
projection_description: "conicConformal" // to be updated with more detailed description
});
// add thrid projection
selectProjection.projection_list.push({
id: 3,
projection_name: "equirectangular", // to be updated with a more descriptive name
projection_function: "equirectangular",
projection_description: "equirectangular" // to be updated with more detailed description
});
selectProjection.projection_list.push({
id: 4,
projection_name: "Mercator", // to be updated with a more descriptive name
projection_function: "mercator",
projection_description: "mercator" // to be updated with more detailed description
});
// the above storage method is used temporary in order to leverage a demo, in production mode, there will be a database table to hold these information
function set_projection(option) {
proj = option.value
projection = eval("d3.geo."+proj+"().scale(500);");
path = d3.geo.path()
.projection(projection);
svg.selectAll("path").transition()
.duration(1000)
.attr("d", path);
/*var link = "https://github.com/mbostock/d3/wiki/Geo-Projections#wiki-" + proj
d3.selectAll("div#current_proj_info").html("Current projection: "+option.text+"");*/
}
function apply_projection(e){
// applying a new projection
set_projection(e.target[e.target.selectedIndex]);
}
var newSelect = document.createElement("select");
newSelect.id = "selectProjection";
newSelect.onchange = apply_projection;
for (var i = selectProjection.projection_list.length - 1; i >= 0; i--) {
console.log(selectProjection.projection_list[i].projection_name);
newSelect[newSelect.length] = new Option(selectProjection.projection_list[i].projection_name, selectProjection.projection_list[i].projection_function, false, false);
};
console.log("newSelect content");
console.log(newSelect);
document.getElementById('projectionList').appendChild(newSelect);
</script>
</body>
</html>
the issue is that when I try to scale graph after applying the new projection, it gets outside of the visible area of the div.
Could you please check what's the issue.

Related

How to zoom faster in a SVG drawing with D3?

I am working on a project with D3.js that displays regions of interest (ROI) which are <g> elements with one <polygon> and one <text>. I noticed that zooming becomes very slow when there are a lot of ROI and it seems that this is mostly because of the texts, i.e. when they are hidden with display: none, zoom is much faster. The zoom speed is different in every browser: Firefox is quite fast, Chrome is average and Edge is slow.
I tried to speed up the text rendering by using the CSS property text-rendering: optimizeSpeed; but the difference is marginal. I noticed that some fonts are faster to render than others. Currently the best results I obtained is by using font-family: monospace;.
So my question is: How to zoom faster in an SVG drawing with D3? Is there a font that is known to be faster to render than others? Or is there a CSS, SVG or D3 trick that could help?
You can test the zoom speed with the snippet. If you click on the button, the text will be hidden an zooming will be much faster.
"use strict";
// Create data with this structure:
// DATA = [{ name: "", coords: [x0, y0, x1, y1, x2, y2, x3, y3]}]
var nbPolyX = 100;
var nbPolyY = 50;
var sqSize = 800 / nbPolyX;
var DATA = [];
for (let idY = 0; idY < nbPolyY; idY++) {
for (let idX = 0; idX < nbPolyX; idX++) {
DATA.push({
name: "x" + idX + "y" + idY,
coords: [
idX * sqSize + 1, idY * sqSize + 1,
(idX + 1) * sqSize - 1, idY * sqSize + 1,
(idX + 1) * sqSize - 1, (idY + 1) * sqSize - 1,
idX * sqSize + 1, (idY + 1) * sqSize - 1
]
})
}
}
var SVGELEM = {};
var ZOOMER = {};
var TRNSF = {
k: 1,
x: 0,
y: 0
};
var ZOOMER = {};
var GZOOM = {};
var ROI = {};
var POLY = {};
var TXT = {};
var BUTTON = {};
addButton();
addSVG();
function addSVG() {
ZOOMER = d3
.zoom()
.scaleExtent([0.9, 40])
.on("zoom", function () {
onZoom();
});
SVGELEM = d3.select("body").append("svg")
.attr("width", nbPolyX * sqSize)
.attr("height", nbPolyY * sqSize)
.call(ZOOMER);
GZOOM = SVGELEM.append("g");
ROI = GZOOM.selectAll("g")
.data(DATA)
.enter()
.append("g")
.classed("roi", true);
POLY = ROI.selectAll("polygon")
.data(function (d) {
return [d.coords];
})
.enter()
.append("polygon")
.attr("points", function (d) {
return d;
});
TXT = ROI.selectAll("text")
.data(function (d) {
var nbElem = d.coords.length;
// Polygon mean point X.
var xMean = 0;
for (let index = 0; index < nbElem - 1; index += 2) {
xMean += d.coords[index];
}
xMean /= nbElem / 2;
// Polygon mean point Y.
var yMean = 0;
for (let index = 1; index < nbElem; index += 2) {
yMean += d.coords[index];
}
yMean /= nbElem / 2;
// Return value.
var ret = {
name: d.name,
x: xMean,
y: yMean
};
return [ret];
})
.enter()
.append("text")
.attr("x", function (d) {
return d.x;
})
.attr("y", function (d) {
return d.y;
})
.text(function (d) {
return d.name;
});
}
function addButton() {
BUTTON = d3.select("body").append("button")
.text("HIDE TEXT")
.on("click", function btnOnClick() {
btnOnClick.state = !btnOnClick.state;
d3.selectAll("text").classed("cl_display_none", btnOnClick.state);
if (btnOnClick.state) d3.select(this).text("SHOW TEXT");
else d3.select(this).text("HIDE TEXT");
});
}
function onZoom() {
if (d3.event !== null) TRNSF = d3.event.transform;
GZOOM.attr(
"transform",
"translate(" + TRNSF.x + "," + TRNSF.y + ") scale(" + TRNSF.k + ")"
);
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title>SVG ZOOM SPEED</title>
<style>
body {
text-align: center;
font-family: monospace;
display: block;
margin: 0 auto;
}
svg {
margin: 10px auto;
border: 1px solid;
display: block;
}
.roi polygon {
shape-rendering: optimizeSpeed;
vector-effect: non-scaling-stroke;
fill: rgba(0, 255, 0, 0.25);
stroke: rgba(0, 255, 0, 1);
stroke-width: 1px;
}
.roi text {
text-rendering: optimizeSpeed;
font-family: monospace;
font-size: 1px;
text-anchor: middle;
dominant-baseline: middle;
}
.cl_display_none {
display: none;
}
button {
width: 150px;
height: 50px;
font-family: monospace;
font-size: 15pt;
margin: 0;
}
</style>
</head>
<body>
<h3>SVG ZOOM SPEED</h3>
<p>Use the mouse wheel to zoom in and out the SVG drawing then hide the text with the button and observe the speed difference. Test it in different browsers.</p>
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/5.7.0/d3.min.js"></script>
<script src="zoom_speed.js"></script>
</body>
</html>

Bar chart to take account of negative values

I have the following data in a csv file called BarData.csv:
Fruit,dt,amount
Apple,12/28/2016,-1256
Apple,12/29/2016,-500
Apple,12/30/2016,3694
Apple,12/31/2016,5586
Apple,1/1/2017,4558
Apple,1/2/2017,6696
Apple,1/3/2017,7757
Apple,1/4/2017,8528
Apple,1/5/2017,5543
Apple,1/6/2017,3363
Apple,1/7/2017,5464
Pear,12/25/2017,250
Pear,12/26/2017,669
Pear,12/27/2017,441
Pear,12/28/2017,159
Pear,12/29/2017,357
Pear,12/30/2017,775
Pear,12/31/2017,669
The following html, css, and javascript is in one .html file:
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-type" content="text/html; charset=utf-8">
<title>BAR SINGLE FUNCTION</title>
<script src="http://d3js.org/d3.v3.js"></script>
<style type="text/css">
#radioDiv {
top: 45px;
font-family: verdana;
font-size: 8px;
width: 455px;
}
#TOPbarChart {
position: absolute;
top: 50px;
left: 30px;
width: 750px;
height: 195px;
}
.axis--y path,
.axis--x path {
display: none;
}
.axis--x line,
.axis--y line {
stroke: black;
fill: none;
stroke-width: 2px
}
.yAxis text,
.xAxis text {
font: 7pt Verdana;
stroke: none;
fill: black;
}
.title,
.titleX {
font-family: Verdana;
font-size: 10px;
}
</style>
</head>
<body>
<div id="radioDiv">
<label>
<input id="radioFrt" type="radio" name="frt" value="Apple" class="radioB" checked> APPLE
</label>
<label>
<input type="radio" name="frt" value="Pear" class="radioB"> PEAR
</label>
</div>
<div id="TOPbarChart"></div>
<script type="text/javascript">
var currentFruit = "Apple";
var currentColr = "#00a5b6";
var barDataCSV_Dly = "BarData.csv";
//
//
// radio button
document.getElementById("radioFrt").checked = true;
d3.selectAll('input[name="frt"]').on("change", function change() {
currentFruit = this.value;
TOPbarChart(currentFruit, currentColr);
});
//FORMATS
var parseDate = d3.time.format("%m/%d/%Y").parse;
//
// BASIC SIZING
//
function barChartBasics() {
var margin = {
top: 25,
right: 35,
bottom: 25,
left: 70
},
width = 550 - margin.left - margin.right,
height = 155 - margin.top - margin.bottom,
colorBar = d3.scale.category20(),
barPaddingFine = 1,
barPaddingThick = 2;
return {
margin: margin,
width: width,
height: height,
colorBar: colorBar,
barPaddingFine: barPaddingFine,
barPaddingThick: barPaddingThick
};
}
// create svg element
var basics = barChartBasics();
var svg = d3.select("#TOPbarChart")
.append("svg")
.attr({
"width": basics.width + basics.margin.left + basics.margin.right,
"height": basics.height + basics.margin.top + basics.margin.bottom,
id: "svgTOPbarChart"
});
// create svg group
var plot = svg
.append("g")
.attr({
"transform": "translate(" + basics.margin.left + "," + basics.margin.top + ")",
id: "svgPlotTOPbarChart"
});
var axisPadding = 2;
var leftAxisGroup = svg
.append('g')
.attr({
transform: 'translate(' + (basics.margin.left - axisPadding) + ',' + (basics.margin.top) + ')',
'class': "yAxis axis--y",
id: "yAxisGTOPbarChart"
});
var bottomAxisGroup = svg
.append('g')
.attr({
'class': "xAxis axis--x",
id: "xAxisGTOPbarChart"
});
var titleTxt = svg.append("text")
.attr({
x: basics.margin.left + 12,
y: 20,
'class': "title",
'text-anchor': "start"
})
// create scales with ranges
var xScale = d3.time.scale().range([0, basics.width]);
var yScale = d3.scale.linear().range([basics.height, 0]);
function TOPbarChart(
frt, colorChosen) {
// get the data
d3.csv(barDataCSV_Dly, function(rows) {
TOPbarData = rows.map(function(d) {
return {
"Fruit": d.Fruit,
"dt": parseDate(d.dt),
"amount": +d.amount
};
}).filter(function(row) {
if (row['Fruit'] == frt) {
return true;
}
});
// create domains for the scales
xScale.domain(d3.extent(TOPbarData, function(d) {
return d.dt;
}));
var amounts = TOPbarData.map(function(d) {
return d.amount;
});
var yMax = d3.max(amounts);
var yMin = d3.min(amounts);
var yMinFinal = 0;
if (yMin < 0) {
yMinFinal = yMin;
}
yScale.domain([yMinFinal, yMax]);
// introduce the bars
// var plot = d3.select("#svgPlotTOPbarChart")
var sel = plot.selectAll("rect")
.data(TOPbarData);
sel.enter()
.append("rect")
.attr({
x: function(d, i) {
return xScale(d.dt);
},
y: function(d) {
return yScale(d.amount);
},
width: (basics.width / TOPbarData.length - basics.barPaddingFine),
height: function(d) {
return basics.height - yScale(d.amount);
},
fill: colorChosen,
'class': "bar"
});
// this little function will create a small ripple affect during transition
var dlyRipple = function(d, i) {
return i * 100;
};
sel
.transition()
.duration(dlyRipple) //1000
.attr({
x: function(d, i) {
return xScale(d.dt);
},
y: function(d) {
return yScale(d.amount);
},
width: (basics.width / TOPbarData.length - basics.barPaddingFine),
height: function(d) {
return basics.height - yScale(d.amount);
},
fill: colorChosen
});
sel.exit().remove();
// add/transition y axis - with ticks and tick markers
var axisY = d3.svg.axis()
.orient('left')
.scale(yScale)
.tickFormat(d3.format("s")) // use abbreviations, e.g. 5M for 5 Million
.outerTickSize(0);
leftAxisGroup.transition().duration(1000).call(axisY);
// add/transition x axis - with ticks and tick markers
var axisX = d3.svg.axis()
.orient('bottom')
.scale(xScale);
bottomAxisGroup
.attr({
transform: 'translate(' + (basics.margin.left + ((basics.width / TOPbarData.length) / 2)) + ',' + (basics.margin.top + basics.height) + ')',
})
.transition().duration(1000).call(axisX.ticks(5));
titleTxt.text("Daily: last " + TOPbarData.length + " days");
// console.log(TOPbarData.length)
});
}
//
//
//
//
TOPbarChart(currentFruit, currentColr);
//
//
//
//
</script>
</body>
</html>
When all the data is positive everything is pretty much ok - but when some of the data is negative we can see the result in this plunker demo:
http://plnkr.co/edit/1hudJYkRq2MnuIlwxXZi?p=preview
How do I amend the code so that:
- the negative bars are shown?
- the base of the positive bars moves vertically up when negative numbers are included?
- the vertical movement is also included in the transition?
Above is more than 1 question but help on any would be appreciated.
The key is to play with the y and height attributes of the bars to position them correctly.
For y, change it to:
y: function(d) {
return yScale(Math.max(0, d.amount));
},
And for the height, change it to:
height: function(d) {
return Math.abs(yScale(d.amount) - yScale(0));
},
You can then style the negative bars to make them a different color.
Check the updated Plunkr - http://plnkr.co/edit/q7dQsPW0PiPuwFTy8gLN?p=preview
Edit:
For the coloring part, you can achieve it with a 1 liner if you want to reduce lines and want more simplicity.
Instead of:
fill: function(d) {
var col = colorChosen
if (d.amount < 0) {
col = "#FF0000";
}
return col;
},
});
You can do:
fill: function(d) {
return d.amount < 0 ? "#FF0000" : colorChosen;
},

D3.js v4 circle radius transition not working as expected

Using D3.js v4, I'm trying to update the radius of a circle on button click.
The problem is that, instead of smooth transitions between the radii the circle is redrawn (going from 'radius1' to 0 and only then to 'radius2') upon each update.
Here's the complete code:
https://jsfiddle.net/4r6hp9my/
Here's the circle update code snippet:
var circles = svg.selectAll('circle').data(dataset);
var enter = circles
.enter()
.append('circle')
.attrs({
cx: w/2,
cy: h/2,
fill: colorsScale,
r: function(d,i){
if(i == myCounter){
var x = rScale(d)
return x;
}
}
});
d3.select('#theButton')
.on('click',function(){
myCounter++
if(myCounter == dataset.length){
myCounter = 0;
};
updateData()
});
function updateData(){
circles
.merge(enter)
.transition()
.attr('r',function(d,i){
if(i == myCounter){
return rScale(d);
}
});
labels
.text(function(d,i){
if(i == myCounter){
return d;
}
});
};
As mentioned by echonax, the issue is you're creating multiple circles based on the dataset. To get the smooth transition, draw only one circle, and update the radius based on 'myCounter'. An example:
var dataset = [2184,2184,3460,2610,2610,2452,842,1349,2430];
var myCounter = 0;
//svg dimensions
var h = 200;
var w = 200;
var svg = d3.select('body')
.append('svg')
.attrs({
width: w,
height: h
})
.classed('middle',true);
//color mapping
var colorsScale = d3.scaleLinear()
.domain([d3.min(dataset),d3.max(dataset)])
.range(['#FFB832','#C61C6F']);
//radius mapping
var rScale = d3.scaleLinear().domain([0, d3.max(dataset)]).range([0,50])
//labels
var label = svg.append("text").attrs({
x: w/2,
y: 20
}).text(function(){ return dataset[myCounter] });
//draw the circles
var circle = svg.append('circle')
.attrs({
cx: w/2,
cy: h/2,
fill: function() { return colorsScale(dataset[myCounter]) },
r: function() { return rScale(dataset[myCounter]) }
});
//button click
d3.select('#theButton')
.on('click',function(){
updateData()
});
function updateData(){
myCounter++;
if ( myCounter > dataset.length - 1 ) myCounter = 0;
circle.transition().attr('r',function(){ return rScale(dataset[myCounter]) }).attr('fill', function() { return colorsScale(dataset[myCounter]) });
label.text(function(){ return dataset[myCounter] });
};
html, body{
height: 100%;
}
.middle{
margin: 100px auto;
}
#theButton{
position: absolute;
left:50px;
top:50px;
}
<script src="https://d3js.org/d3.v4.js"></script>
<script src="https://d3js.org/d3-selection-multi.v1.min.js"></script>
<button id="theButton" type="button">Click Me!</button>
Based on your data, there are a couple of times that the circle won't change as the data is the same, but the transition should work when it does.

Leaflet Markercluster showCoverageOnHover triggered wrong

I am using markerCluster for Leaflet with the showCoverageOnHover option set to true. However, in Firefox (v 46.0.1), the event showCoverageOnHover is not triggered correctly, meaning that the cluster area is shown not only when the mouse is hovered over the cluster, but also if the mouse is far away from that cluster.
Basically, I am using the standard procedure to create a markerClusterGroup, but with a customized icon creation function (Using d3 to draw a Pie chart). My code looks as follows:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<style type="text/css">
#mapid {
height: 60vh;
}
</style>
<script src='https://api.mapbox.com/mapbox.js/v2.4.0/mapbox.js'></script>
<link href='https://api.mapbox.com/mapbox.js/v2.4.0/mapbox.css' rel='stylesheet' />
<script src='https://cdnjs.cloudflare.com/ajax/libs/leaflet.markercluster/0.5.0/leaflet.markercluster.js'></script>
<link href='https://cdnjs.cloudflare.com/ajax/libs/leaflet.markercluster/0.5.0/MarkerCluster.css' rel='stylesheet' />
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js"></script>
<title>WorldMap</title>
<script type="text/javascript">
function defineClusterIcon(cluster) {
var color = d3.scale.category20b();
//some dummy json
var myjson = '[{ "label":"Monday", "count": 15 },{ "label":"Tuesday", "count": 20 }]';
var dataset = JSON.parse( myjson );
var size = 40;
var radius= size / 2;
var svgres = document.createElementNS(d3.ns.prefix.svg, 'svg');
var svg = d3.select(svgres).append('svg')
.attr('width', size)
.attr('height', size)
.append('g')
.attr('transform','translate(' + (size / 2) + ',' + (size / 2) + ')'); //center g
var arc = d3.svg.arc().outerRadius(radius);
var pie = d3.layout.pie().value(function(d) {
return d.count;
});
//create final chart
svg.selectAll('path').data(pie(dataset)) //fill dataset into path
.enter() //create placeholder for data
.append('path') //fill placeholder with data in path
.attr('d', arc) //define an attribute d
.attr('fill', function(d, i) {
return color(d.data.label);
});
var html = serializeXmlNode(svgres);
var myIcon = new L.DivIcon({
html : html,
className : 'mycluster',
iconSize : new L.Point(size, size)
});
return myIcon;
}
function serializeXmlNode(xmlNode) {
if (typeof window.XMLSerializer != "undefined") {
return (new window.XMLSerializer()).serializeToString(xmlNode);
} else if (typeof xmlNode.xml != "undefined") {
return xmlNode.xml;
}
return "";
}
</script>
</head>
<body>
<div id="mapid"></div>
<script type="text/javascript">
var map = L.map('mapid', {
center: [40, 40],
maxZoom : 10,
zoom: 2
});
//create markercluster
var markers = new L.markerClusterGroup({
showCoverageOnHover: true,
iconCreateFunction: defineClusterIcon
});
//some example markers
var marker = new L.marker([40.0,10.0]);
markers.addLayer(marker);
var marker = new L.marker([42.0,-12.0]);
markers.addLayer(marker);
var marker = new L.marker([50.0,30.0]);
markers.addLayer(marker);
map.addLayer(markers);
</script>
</body>
</html>
Any ideas why the showCoverageOnHover event is not triggered correctly in Firefox?
Thanks!
Looks like the SVG element you created overflows the Leaflet icon.
Simply setting overflow: hidden CSS rule on your icon class seems to solve your issue.
.mycluster {
overflow: hidden;
}
Updated JSFiddle: https://jsfiddle.net/sqeypmrn/1/
Note: question also posted on Leaflet.markercluser GitHub page as issue #677.

How to remove lines in between cartogram Maps in d3.js

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.
We had the same problem a year or so back and it is due to the arcs in the topojson file moving from 180 or 360 back to 0, basically wrapping at the ends of the map.
We needed to manually go into the map file and edit it using QGIS.
This resolved the issue of the lines.
You will also find if you are using the Cartogram code that the map of the world is far to detailed than you will need given you will be distorting the map anyway. If you are generating the cartogram in real time then you will face delays in the code.
You should probably reduce the complexity of the map too.
Here is an example of the JSON we used to create real time hexagonal cartograms in the browser.
Simplified World Map JSON

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