我目前正在努力分拆d3noob页面：http://www.d3noob.org/2014/07/d3js-multi-line-graph-with-automatic.html
除了两个元素外，它几乎是一个完全相同的副本。一，我试图加载JSON文件而不是D3Noob的首选CSV。我还想知道使用扁平或嵌套的JSON文件是否更容易。如果嵌套会更好，有人可以解释或指导我到某个地方解释d3中的嵌套JSON比我一直在寻找的更好吗？那太棒了。
总结一下。 1.如何加载JSON代替CSV 2.嵌套还是扁平？
提前谢谢！
代码：
<!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>
答案 0 :(得分：0)
答案很简单，我应该早点意识到这一点。虽然我正确地做了一切，但它没有用。我的问题是我的代码处于头脑中，我试图在没有身体存在的情况下将SVG附加到身体上。我唯一要做的就是将所有的head脚本放到一个函数中，然后在加载body时调用该函数。
<!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>