Loading JSON in Place of CSV D3 - javascript

I'm currently working on a spin-off of d3noob's page here: http://www.d3noob.org/2014/07/d3js-multi-line-graph-with-automatic.html
It's almost an identical copy except for two elements. One, I'm trying to load a JSON file instead of D3Noob's preferred CSV. I also want to know if it is easier to use a flat or nested JSON file. If nested would be better, can someone explain or direct me to somewhere that explains nested JSON in d3 a little bit better than what I have been looking for? That'd be great.
Just to sum up. 1. How to load JSON in place of a CSV 2. Nested or flat?
Nested Data
Flat Data
Thank you in advance!
Code:
<!DOCTYPE html>
<html>
<meta charset="utf-8">
<head>
<style> /* set the CSS */
body { font: 12px Arial;}
path {
stroke: steelblue;
stroke-width: 2;
fill: none;
}
.axis path,
.axis line {
fill: none;
stroke: none;
stroke-width: 1;
shape-rendering: crispEdges;
}
.axis text {
fill:red;
}
.legend {
font-size: 16px;
font-weight: bold;
text-anchor: middle;
}
</style>
<script src="d3.js"></script>
<script>
function init(){
// Set the dimensions of the canvas / graph
var margin = {top: 30, right: 20, bottom: 70, left: 50},
width = 600 - margin.left - margin.right,
height = 300 - margin.top - margin.bottom;
// Set the ranges
var x = d3.time.scale().range([0, width]);
var y = d3.scale.linear().range([height, 0]);
// Define the axes
var xAxis = d3.svg.axis().scale(x)
.orient("bottom").ticks(5);
var yAxis = d3.svg.axis().scale(y)
.orient("left").ticks(5);
// Define the line
var valline = d3.svg.line()
.x(function(d) { return x(d.week); })
.y(function(d) { return y(d.val); });
// Adds the svg canvas
var svg = d3.select("body")
.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 + ")");
// Get the data
d3.json("data.01.json", function(error, data) {
data.chartdata.forEach(function(d) {
d.week = d.week;
d.val = +d.val;
});
// Scale the range of the data
x.domain(d3.extent(data.chartdata, function(d) { return d.week; }));
y.domain([0, d3.max(data.chartdata, function(d) { return d.val; })]);
// Nest the entries by name
var dataNest = d3.nest()
.key(function(d) {return d.name;})
.entries(data.chartdata);
var color = d3.scale.category10(); // set the colour scale
legendSpace = width/dataNest.length; // spacing for the legend
// Loop through each name / key
dataNest.forEach(function(d,i) {
svg.append("path")
.attr("class", "line")
.style("stroke", function() { // Add the colours dynamically
return d.color = color(d.key); })
.attr("id", 'tag'+d.key.replace(/\s+/g, '')) // assign ID
.attr("d", valline(d.values));
// Add the Legend
svg.append("text")
.attr("x", (legendSpace/2)+i*legendSpace) // space legend
.attr("y", height + (margin.bottom/2)+ 5)
.attr("class", "legend") // style the legend
.style("fill", function() { // Add the colours dynamically
return d.color = color(d.key); })
.on("click", function(){
// Determine if current line is visible
var active = d.active ? false : true,
newOpacity = active ? 0 : 1;
// Hide or show the elements based on the ID
d3.select("#tag"+d.key.replace(/\s+/g, ''))
.transition().duration(100)
.style("opacity", newOpacity);
// Upweek whether or not the elements are active
d.active = active;
})
.text(d.key);
});
// Add the X Axis
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
// Add the Y Axis
svg.append("g")
.attr("class", "y axis")
.call(yAxis);
});
}
</script>
</head>
<body onload="init()">
<!-- load the d3.js library -->
</body>
</html>

The answer is rather simple and I should have realized it earlier. Though I was doing everything correctly, it wasn't working. My problem was that my code was in the head and I was trying to append an SVG to the body without the body existing yet. The only thing I had to do was make all of the head script into a function and call the function when the body loaded, as such.
<!DOCTYPE html>
<html>
<meta charset="utf-8">
<head>
<style> /* set the CSS */
body { font: 12px Arial;}
path {
stroke: steelblue;
stroke-width: 2;
fill: none;
}
.axis path,
.axis line {
fill: none;
stroke: none;
stroke-width: 1;
shape-rendering: crispEdges;
}
.axis text {
fill:red;
}
.legend {
font-size: 16px;
font-weight: bold;
text-anchor: middle;
}
</style>
<script src="d3.js"></script>
<script>
function init(){
// Set the dimensions of the canvas / graph
var margin = {top: 30, right: 20, bottom: 70, left: 50},
width = 600 - margin.left - margin.right,
height = 300 - margin.top - margin.bottom;
// Set the ranges
var x = d3.time.scale().range([0, width]);
var y = d3.scale.linear().range([height, 0]);
// Define the axes
var xAxis = d3.svg.axis().scale(x)
.orient("bottom").ticks(5);
var yAxis = d3.svg.axis().scale(y)
.orient("left").ticks(5);
// Define the line
var valline = d3.svg.line()
.x(function(d) { return x(d.week); })
.y(function(d) { return y(d.val); });
// Adds the svg canvas
var svg = d3.select("body")
.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 + ")");
// Get the data
d3.json("data.01.json", function(error, data) {
data.chartdata.forEach(function(d) {
d.week = d.week;
d.val = +d.val;
});
// Scale the range of the data
x.domain(d3.extent(data.chartdata, function(d) { return d.week; }));
y.domain([0, d3.max(data.chartdata, function(d) { return d.val; })]);
// Nest the entries by name
var dataNest = d3.nest()
.key(function(d) {return d.name;})
.entries(data.chartdata);
var color = d3.scale.category10(); // set the colour scale
legendSpace = width/dataNest.length; // spacing for the legend
// Loop through each name / key
dataNest.forEach(function(d,i) {
svg.append("path")
.attr("class", "line")
.style("stroke", function() { // Add the colours dynamically
return d.color = color(d.key); })
.attr("id", 'tag'+d.key.replace(/\s+/g, '')) // assign ID
.attr("d", valline(d.values));
// Add the Legend
svg.append("text")
.attr("x", (legendSpace/2)+i*legendSpace) // space legend
.attr("y", height + (margin.bottom/2)+ 5)
.attr("class", "legend") // style the legend
.style("fill", function() { // Add the colours dynamically
return d.color = color(d.key); })
.on("click", function(){
// Determine if current line is visible
var active = d.active ? false : true,
newOpacity = active ? 0 : 1;
// Hide or show the elements based on the ID
d3.select("#tag"+d.key.replace(/\s+/g, ''))
.transition().duration(100)
.style("opacity", newOpacity);
// Upweek whether or not the elements are active
d.active = active;
})
.text(d.key);
});
// Add the X Axis
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
// Add the Y Axis
svg.append("g")
.attr("class", "y axis")
.call(yAxis);
});
}
</script>
</head>
<body onload="init()">
<!-- load the d3.js library -->
</body>
</html>

Related

How do i use multiple csv files here and make the graph update itself every 5 seconds?

Here is my code. I m currently using 2 csv files and when i add third one nothing appears on the screen. How do i add multiple csv files here?
Graph should update itself for each csv files in every 5 seconds.
I need your help, what code has to be added to make it even more dynamic.
I tried this part in code to make it work with 3 csv, But it din work.
function updateData() {
// Get the data again
d3.csv("data-alt.csv", function(error, data) {
d3.csv("alt.csv-data", function(error, data) {
data.forEach(function(d) {
d.date = parseDate(d.date);
d.close = +d.close;
});
Here is the overall code.
<!DOCTYPE html>
<meta charset="utf-8">
<style> /* set the CSS */
body { font: 12px Arial;}
path {
stroke: steelblue;
stroke-width: 2;
fill: none;
}
.axis path,
.axis line {
fill: none;
stroke: grey;
stroke-width: 1;
shape-rendering: crispEdges;
}
</style>
<body>
<!-- load the d3.js library -->
<script src="http://d3js.org/d3.v3.min.js"></script>
<script>
// Set the dimensions of the canvas / graph
var margin = {top: 30, right: 20, bottom: 30, left: 50},
width = 600 - margin.left - margin.right,
height = 270 - margin.top - margin.bottom;
// Parse the date / time
var parseDate = d3.time.format("%d-%b-%y").parse;
// Set the ranges
var x = d3.time.scale().range([0, width]);
var y = d3.scale.linear().range([height, 0]);
// Define the axes
var xAxis = d3.svg.axis().scale(x)
.orient("bottom").ticks(5);
var yAxis = d3.svg.axis().scale(y)
.orient("left").ticks(5);
// Define the line
var valueline = d3.svg.line()
.x(function(d) { return x(d.date); })
.y(function(d) { return y(d.close); });
// Adds the svg canvas
var svg = d3.select("body")
.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 + ")");
// Get the data
d3.csv("data.csv", function(error, data) {
data.forEach(function(d) {
d.date = parseDate(d.date);
d.close = +d.close;
});
// Scale the range of the data
x.domain(d3.extent(data, function(d) { return d.date; }));
y.domain([0, d3.max(data, function(d) { return d.close; })]);
// Add the valueline path.
svg.append("path")
.attr("class", "line")
.attr("d", valueline(data));
// Add the X Axis
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
// Add the Y Axis
svg.append("g")
.attr("class", "y axis")
.call(yAxis);
});
var inter = setInterval(function() {
updateData();
}, 5000);
// ** Update data section (Called from the onclick)
function updateData() {
// Get the data again
d3.csv("data-alt.csv", function(error, data) {
data.forEach(function(d) {
d.date = parseDate(d.date);
d.close = +d.close;
});
// Scale the range of the data again
x.domain(d3.extent(data, function(d) { return d.date; }));
y.domain([0, d3.max(data, function(d) { return d.close; })]);
// Select the section we want to apply our changes to
var svg = d3.select("body").transition();
// Make the changes
svg.select(".line") // change the line
.duration(750)
.attr("d", valueline(data));
svg.select(".x.axis") // change the x axis
.duration(750)
.call(xAxis);
svg.select(".y.axis") // change the y axis
.duration(750)
.call(yAxis);
});
}
</script>
</body>
You should break your function that handles parsing the result into another function, then just call d3.csv multiple times passing in the correct URL for the csv and the specific handler for that csv file.
Here is a quick snippet with the changes i suggested:
// Set the dimensions of the canvas / graph
var margin = {
top: 30,
right: 20,
bottom: 30,
left: 50
},
width = 600 - margin.left - margin.right,
height = 270 - margin.top - margin.bottom;
// Parse the date / time
var parseDate = d3.time.format("%d-%b-%y").parse;
// Set the ranges
var x = d3.time.scale().range([0, width]);
var y = d3.scale.linear().range([height, 0]);
// Define the axes
var xAxis = d3.svg.axis().scale(x)
.orient("bottom").ticks(5);
var yAxis = d3.svg.axis().scale(y)
.orient("left").ticks(5);
// Define the line
var valueline = d3.svg.line()
.x(function(d) {
return x(d.date);
})
.y(function(d) {
return y(d.close);
});
// Adds the svg canvas
var svg = d3.select("body")
.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 + ")");
function processDataCsv(error, data) {
data.forEach(function(d) {
d.date = parseDate(d.date);
d.close = +d.close;
});
// Scale the range of the data
x.domain(d3.extent(data, function(d) {
return d.date;
}));
y.domain([0, d3.max(data, function(d) {
return d.close;
})]);
// Add the valueline path.
svg.append("path")
.attr("class", "line")
.attr("d", valueline(data));
// Add the X Axis
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
// Add the Y Axis
svg.append("g")
.attr("class", "y axis")
.call(yAxis);
}
function processAnotherCsv(error, data) {
// TODO: implement processing
}
function processYetAnotherCsv(error, data) {
// TODO: implement processing
}
// ** Update data section (Called from the onclick)
function updateData() {
// Get the data again
d3.csv("data.csv", processDataCsv);
d3.csv("another.csv", processAnotherCsv);
d3.csv("yetAnother.csv", processYetAnotherCsv);
}
// Get the data, just use the function you already wrote to do that
updateData();
var inter = setInterval(function() {
updateData();
}, 5000);
body {
font: 12px Arial;
}
path {
stroke: steelblue;
stroke-width: 2;
fill: none;
}
.axis path,
.axis line {
fill: none;
stroke: grey;
stroke-width: 1;
shape-rendering: crispEdges;
}
<script src="http://d3js.org/d3.v3.min.js"></script>

D3 shift ticks to align with axis

I'm trying to create a d3 line chart that displays monthly data. The chart draws but the ticks on the x-axis are shifted and don't align with the data points drawn. As you can see from the screenshot, the ticks are shifted right from the data points.
I've tried figuring out how to transform-translate the ticks but without luck. Thanks!
Here is a screenshot.
Here is my code:
// set the dimensions and margins of the graph
var margin = {top: 20, right: 20, bottom: 50, left: 50},
width = 960 - margin.left - margin.right,
height = 500 - margin.top - margin.bottom;
// set the ranges
var x = d3.scaleBand().range([0, width]);
var y = d3.scaleLinear().range([height, 0]);
// define the line
var valueline = d3.line().x(function(d) { return x(d.month); })
.y(function(d) { return y(d.average); });
// append the svg obgect to the body of the page
// appends a 'group' element to 'svg'
// moves the 'group' element to the top left margin
var svg = d3.select("#chart")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.append("g")
.attr("transform",
"translate(" + margin.left + "," + margin.top + ")");
// Get the data
var data = [{"month":"january","average":0},{"month":"february","average":0},{"month":"march","average":0},{"month":"april","average":9.0},{"month":"may","average":892.0},{"month":"june","average":10.0},{"month":"july","average":92.0},{"month":"august","average":9281.0},{"month":"september","average":8402.0},{"month":"october","average":823213.0},{"month":"november","average":82.0},{"month":"december","average":0}];
x.domain(data.map(function(d) { return d.month; }));
y.domain([0, d3.max(data, function(d) { return d.average; })]);
// Add the valueline path.
console.log(valueline);
svg.append("path")
.data([data])
.attr("class", "line")
.attr("d", valueline);
// Add the X Axis
svg.append("g")
.attr("class", "e4rAxis")
.attr("transform", "translate(0," + height + ")")
.call(d3.axisBottom(x))
.selectAll("text")
.style("text-anchor", "end")
.attr("dx", "-.8em")
.attr("dy", ".15em")
.attr("transform", "rotate(-65)");
// xAxisElement.selectAll(".tick").attr("transform", "translate(0,-5)");
// Add the Y Axis
svg.append("g")
.call(d3.axisLeft(y));
svg.selectAll("dot")
.data(data)
.enter().append("circle")
.attr("r", 5)
.attr("cx", function(d) { return x(d.month); })
.attr("cy", function(d) { return y(d.average); });
.line {
fill: none;
stroke: steelblue;
stroke-width: 2px;
}
.axis path, .axis line {
fill: none;
shape-rendering: crispEdges;
}
.line {
}
.area {
fill: steelblue;
opacity: 0.5;
}
.dot {
fill: steelblue;
stroke: steelblue;
stroke-width: 1.5px;
}
<script src="https://d3js.org/d3.v4.min.js"></script>
<svg width="960" height="500" id="chart"></svg>
There are 2 ways to fix your issue.
Hard code and set some padding for your line and circles so they align with your x axis.
// define the line
var valueline = d3.line().x(function(d) {
return x(d.month) + 38; //set x padding of 38
})
.y(function(d) {
return y(d.average);
});
svg.selectAll("dot")
.data(data)
.enter().append("circle")
.attr("r", 5)
.attr("cx", function(d) {
return x(d.month) + 38;
})
.attr("cy", function(d) {
return y(d.average);
});
JSFiddle - https://jsfiddle.net/L5dctwsz/
Use d3.scaleTime since you're dealing with month names which will solve the issue.
Set it like the following:
var x = d3.scaleTime().range([0, width]);
Parse the month and then set the domain:
// parse the date / time
var parseMonth = d3.timeParse("%B");
data.forEach(function(d) {
d.month = parseMonth(d.month);
});
x.domain(d3.extent(data, function(d) {
return d.month;
}));
JSFiddle - https://jsfiddle.net/pm7gLn2u/

Is there a way to parse times and be able to plot them directly using javascript and d3?

How can I make a scatterplot plotting time of day against date, which looks like this in using javascript and d3? The problem I am having is formatting the time of day data and axis. Input of the date is in the y column format below.
Sample data:
Day Time
5-Feb-16 21:35:00
5-Feb-16 19:15:00
11-Dec-15 21:42:00
21-Jul-15 11:00:00
Code below inspired by:
http://bl.ocks.org/d3noob/38744a17f9c0141bcd04
What I have so far:
<!DOCTYPE html>
<meta charset="utf-8">
<style> /* set the CSS */
body { font: 12px Arial;}
path {
stroke: steelblue;
stroke-width: 2;
fill: none;
}
.axis path,
.axis line {
fill: none;
stroke: grey;
stroke-width: 1;
shape-rendering: crispEdges;
}
</style>
<body>
<!-- load the d3.js library -->
<script src="http://d3js.org/d3.v3.min.js"></script>
<script>
// Set the dimensions of the canvas / graph
var margin = {top: 30, right: 20, bottom: 30, left: 50},
width = 600 - margin.left - margin.right,
height = 270 - margin.top - margin.bottom;
// Parse the date / time
var parseDate = d3.time.format("%d-%b-%y").parse;
// Set the ranges
var x = d3.time.scale().range([0, width]);
var y = d3.scale.linear().range([height, 0]);
// Define the axes
var xAxis = d3.svg.axis().scale(x)
.orient("bottom").ticks(5);
var yAxis = d3.svg.axis().scale(y)
.orient("left").ticks(5);
// Define the line
var valueline = d3.svg.line()
.x(function(d) { return x(d.Day); })
.y(function(d) { return y(d.Time); });
// Adds the svg canvas
var svg = d3.select("body")
.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 + ")");
// Get the data
d3.csv("data.csv", function(error, data) {
data.forEach(function(d) {
console.log(d.Time);
d.Day = parseDate(d.Day);
d.Time = +d.Time;
});
// Scale the range of the data
x.domain(d3.extent(data, function(d) { return d.Day; }));
y.domain([0, d3.max(data, function(d) { return d.Time; })]);
// Add the valueline path.
svg.append("path")
.attr("class", "line")
.attr("d", valueline(data));
// Add the scatterplot
svg.selectAll("dot")
.data(data)
.enter().append("circle")
.attr("r", 3.5)
.attr("cx", function(d) { return x(d.Day); })
.attr("cy", function(d) { return y(d.Time); });
// Add the X Axis
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
// Add the Y Axis
svg.append("g")
.attr("class", "y axis")
.call(yAxis);
});
</script>
</body>
My output:
Is there a way to parse times and be able to plot them directly using javascript and d3? Or do I need to convert them to decimal numbers like 12:30 = 12.5 to plot them?
If you're using time in the y scale, you should parse the Time column as well:
var parseDate = d3.time.format("%d-%b-%y").parse;
var parseTime = d3.time.format("%H:%M:%S").parse;
Here is your code with just 4 points (the ones of the CSV you copy/pasted in your question):
var margin = {
top: 30,
right: 20,
bottom: 30,
left: 80
},
width = 600 - margin.left - margin.right,
height = 270 - margin.top - margin.bottom;
// Parse the date / time
var parseDate = d3.time.format("%d-%b-%y").parse;
var parseTime = d3.time.format("%H:%M:%S").parse;
// Set the ranges
var x = d3.time.scale().range([0, width]);
var y = d3.time.scale().range([height, 0]);
// Define the axes
var xAxis = d3.svg.axis().scale(x)
.orient("bottom").ticks(5);
var yAxis = d3.svg.axis().scale(y)
.orient("left");
// Define the line
var valueline = d3.svg.line()
.x(function(d) {
return x(d.Day);
})
.y(function(d) {
return y(d.Time);
});
// Adds the svg canvas
var svg = d3.select("body")
.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 + ")");
// Get the data
var data = d3.csv.parse(d3.select("#csv").text());
data.forEach(function(d) {
d.Day = parseDate(d.Day);
d.Time = parseTime(d.Time);
});
// Scale the range of the data
x.domain(d3.extent(data, function(d) {
return d.Day;
}));
y.domain([parseTime("00:00:01"), parseTime("23:59:59")]);
// Add the valueline path.
svg.append("path")
.attr("class", "line")
.attr("d", valueline(data));
// Add the scatterplot
svg.selectAll("dot")
.data(data)
.enter().append("circle")
.attr("r", 3.5)
.attr("cx", function(d) {
return x(d.Day);
})
.attr("cy", function(d) {
return y(d.Time);
});
// Add the X Axis
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
// Add the Y Axis
svg.append("g")
.attr("class", "y axis")
.call(yAxis);
pre {
display: none;
}
path {
stroke: steelblue;
stroke-width: 2;
fill: none;
}
.axis path,
.axis line {
fill: none;
stroke: grey;
stroke-width: 1;
shape-rendering: crispEdges;
}
<script src="//d3js.org/d3.v3.min.js"></script>
<pre id="csv">Day,Time
5-Feb-16,21:35:00
1-Feb-16,19:15:00
11-Dec-15,21:42:00
21-Jul-15,11:00:00</pre>

D3 Line Chart Show/Hide Element, Variable Not Defined Error?

I'm using code similar to this one, and actually plugged in this code to see if I get the same error and I do. This is the code:
<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
font: 12px Arial;
}
path {
stroke: steelblue;
stroke-width: 2;
fill: none;
}
.axis path,
.axis line {
fill: none;
stroke: grey;
stroke-width: 1;
shape-rendering: crispEdges;
}
.legend {
font-size: 16px;
font-weight: bold;
text-anchor: start;
}
</style>
<body>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script>
var margin = {top: 30, right: 40, bottom: 70, left: 50},
width = 600 - margin.left - margin.right,
height = 300 - margin.top - margin.bottom;
var parseDate = d3.time.format("%d-%b-%y").parse;
var x = d3.time.scale().range([0, width]);
var y0 = d3.scale.linear().range([height, 0]);
var y1 = d3.scale.linear().range([height, 0]);
var xAxis = d3.svg.axis().scale(x)
.orient("bottom").ticks(5);
var yAxisLeft = d3.svg.axis().scale(y0)
.orient("left").ticks(5);
var yAxisRight = d3.svg.axis().scale(y1)
.orient("right").ticks(5);
var valueline = d3.svg.line()
.x(function(d) { return x(d.date); })
.y(function(d) { return y0(d.close); });
var valueline2 = d3.svg.line()
.x(function(d) { return x(d.date); })
.y(function(d) { return y1(d.open); });
var svg = d3.select("body")
.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 data = [
{"date":"9-Apr-12","close":436,"open":9.04},
{"date":"7-Apr-12","close":221,"open":4.02},
{"date":"5-Apr-12","close":113,"open":9.02},
{"date":"4-Apr-12","close":64,"open":32.05},
{"date":"3-Apr-12","close":29,"open":46.03},
{"date":"2-Apr-12","close":18,"open":51.03}
];
// Get the data
data.forEach(function(d) {
d.date = parseDate(d.date);
d.close = +d.close;
d.open = +d.open;
});
// Scale the range of the data
x.domain(d3.extent(data, function(d) { return d.date; }));
y0.domain([0, d3.max(data, function(d) {
return Math.max(d.close); })]);
y1.domain([0, d3.max(data, function(d) {
return Math.max(d.open); })]);
svg.append("path")
.attr("class", "line")
.attr("id", "blueLine")
.attr("d", valueline(data));
svg.append("path")
.attr("class", "line")
.style("stroke", "red")
.attr("id", "redLine")
.attr("d", valueline2(data));
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
// edit the Y Axis Left
svg.append("g")
.attr("class", "y axis")
.style("fill", "steelblue")
.attr("id", "blueAxis")
.call(yAxisLeft);
svg.append("g")
.attr("class", "y axis")
.attr("transform", "translate(" + width + " ,0)")
.style("fill", "red")
.attr("id", "redAxis")
.call(yAxisRight);
// Add the blue line title
svg.append("text")
.attr("x", 0)
.attr("y", height + margin.top + 10)
.attr("class", "legend")
.style("fill", "steelblue")
.on("click", function(){
// Determine if current line is visible
var active = blueLine.active ? false : true,
newOpacity = active ? 0 : 1;
// Hide or show the elements
d3.select("#blueLine").style("opacity", newOpacity);
d3.select("#blueAxis").style("opacity", newOpacity);
// Update whether or not the elements are active
blueLine.active = active;
})
.text("Blue Line");
// Add the red line title
svg.append("text")
.attr("x", 0)
.attr("y", height + margin.top + 30)
.attr("class", "legend")
.style("fill", "red")
.on("click", function(){
// Determine if current line is visible
var active = redLine.active ? false : true ,
newOpacity = active ? 0 : 1;
// Hide or show the elements
d3.select("#redLine").style("opacity", newOpacity);
d3.select("#redAxis").style("opacity", newOpacity);
// Update whether or not the elements are active
redLine.active = active;
})
.text("Red Line");
</script>
</body>
I'm getting errors saying that 'blueline' and 'redline' are not defined.
Where do I define those?
I've looked at similar code where the html, css, and js are separated into their own files which is how I've done it also, and other than what I see in the code above I don't find those variables used anyplace else or defined beyond what is there.
I made a plunk with the code you have there and everything works just fine. Let me explain a little of what is going on though.
Instead of using HTML that is already there, D3 will often generate its own (in fact it has to generate its own to do the visualizations). You see this with statements like the following:
svg.append("path")
.attr("class", "line")
.attr("id", "blueLine")
.attr("d", valueline(data));
D3 just created a path element and appended it to the svg element it created earlier. It gives this particular element an id of blueLine which it uses later to apply styles. It did not exist in any HTML prior to this script running. D3 created it.

Time Parse Error in d3.js?

I'm trying to run a basic d3.js line graph but I keep getting an error in the function d3_time_parse. The example I'm attempting to copy is here: http://bl.ocks.org/d3noob/b3ff6ae1c120eea654b5
Specifically, the error is d3.v3.js:2550 Uncaught TypeError: Cannot read property 'length' of undefined corresponding to
2549: function d3_time_parse(date, template, string, j) {
2550: var c, p, t, i = 0, n = template.length, m = string.length;
My code:
<!DOCTYPE html>
<meta charset="utf-8">
<style> /* set the CSS */
body { font: 12px Arial;}
path {
stroke: steelblue;
stroke-width: 2;
fill: none;
}
.axis path,
.axis line {
fill: none;
stroke: grey;
stroke-width: 1;
shape-rendering: crispEdges;
}
</style>
<body>
<!-- load the d3.js library -->
<script src="http://d3js.org/d3.v3.js"></script>
<script>
// Set the dimensions of the canvas / graph
var margin = {top: 30, right: 20, bottom: 30, left: 50},
width = 600 - margin.left - margin.right,
height = 270 - margin.top - margin.bottom;
// Parse the date / time
var parseDate = d3.time.format("%d-%b-%y").parse;
// Set the ranges
var x = d3.time.scale().range([0, width]);
var y = d3.scale.linear().range([height, 0]);
// Define the axes
var xAxis = d3.svg.axis().scale(x)
.orient("bottom").ticks(5);
var yAxis = d3.svg.axis().scale(y)
.orient("left").ticks(5);
// Define the line
var valueline = d3.svg.line()
.x(function(d) { return x(d.date); })
.y(function(d) { return y(d.close); });
// Adds the svg canvas
var svg = d3.select("body")
.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 + ")");
// Get the data
d3.csv("data.csv", function(error, data) {
data.forEach(function(d) {
d.date = parseDate(d.date);
d.close = +d.close;
});
// Scale the range of the data
x.domain(d3.extent(data, function(d) { return d.date; }));
y.domain([0, d3.max(data, function(d) { return d.close; })]);
// Add the valueline path.
svg.append("path")
.attr("class", "line")
.attr("d", valueline(data));
// Add the X Axis
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
// Add the Y Axis
svg.append("g")
.attr("class", "y axis")
.call(yAxis);
});
</script>
</body>
data.csv
date,close
1-May-12,58.13
30-Apr-12,53.98
27-Apr-12,67.00
26-Apr-12,89.70
25-Apr-12,99.00
24-Apr-12,130.28
23-Apr-12,166.70
20-Apr-12,234.98
19-Apr-12,345.44
18-Apr-12,443.34
17-Apr-12,543.70
16-Apr-12,580.13
13-Apr-12,605.23
12-Apr-12,622.77
11-Apr-12,626.20
10-Apr-12,628.44
9-Apr-12,636.23
5-Apr-12,633.68
4-Apr-12,624.31
3-Apr-12,629.32
2-Apr-12,618.63
30-Mar-12,599.55
29-Mar-12,609.86
28-Mar-12,617.62
27-Mar-12,614.48
26-Mar-12,606.98
A few users have asked similar questions, and the issues were fixed after correcting the time format used in var parseDate and making sure the CSV values are separated by commas. I've checked for these issues and still no luck.
I determined there was an issue with the .csv file after I downloaded the data file from the example website I was using.
Although the .csv files look identical in excel, the code only runs when I use the file downloaded from the example site.

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