问题
I have modified some code available on the internet to draw a line chart based on the data contained in the array "data".
<!doctype html>
<html>
<head>
<title></title>
</head>
<body>
<style>
.chart-line {
fill: none;
stroke : #0ff;
shape-rendering: crispEdges;
}
</style>
<script src="https://d3js.org/d3.v4.min.js"> </script>
<script>
var svg = d3.select("svg"),
margin = { top: 20, right: 20, bottom: 30, left: 50 },
width = +svg.attr("width") - margin.left - margin.right,
height = +svg.attr("height") - margin.top - margin.bottom,
g = svg.append("g").attr("transform", "translate(" + margin.left + "," + margin.top + ")");
var parseTime = d3.timeParse("%d-%b-%y");
var x = d3.scaleTime()
.rangeRound([0, width]);
var y = d3.scaleLinear()
.rangeRound([height, 0]);
var line = d3.line()
.x(function (d) { return x(d.date); })
.y(function (d) { return y(d.close); });
var data = [
{ letter: "A", frequency: .08167 },
{ letter: "B", frequency: .01492 },
{ letter: "C", frequency: .02780 },
{ letter: "D", frequency: .04253 },
{ letter: "E", frequency: .12702 },
{ letter: "F", frequency: .02288 },
{ letter: "G", frequency: .02022 },
{ letter: "H", frequency: .06094 },
{ letter: "I", frequency: .06973 },
{ letter: "J", frequency: .00153 },
{ letter: "K", frequency: .00747 },
{ letter: "L", frequency: .04025 },
{ letter: "M", frequency: .02517 },
{ letter: "N", frequency: .06749 },
{ letter: "O", frequency: .07507 },
{ letter: "P", frequency: .01929 },
{ letter: "Q", frequency: .00098 },
{ letter: "R", frequency: .05987 },
{ letter: "S", frequency: .06333 },
{ letter: "T", frequency: .09056 },
{ letter: "U", frequency: .02758 },
{ letter: "V", frequency: .01037 },
{ letter: "W", frequency: .02465 },
{ letter: "X", frequency: .00150 },
{ letter: "Y", frequency: .01971 },
{ letter: "Z", frequency: .00074 }
];
x.domain(data.map(function (d) { return d.letter; }));
y.domain([0, d3.max(data, function (d) { return d.frequency;
})]);
g.append("g")
.attr("transform", "translate(0," + height + ")")
.call(d3.axisBottom(x))
.select(".domain")
.remove();
g.append("g")
.call(d3.axisLeft(y))
.append("text")
.attr("fill", "#000")
.attr("transform", "rotate(-90)")
.attr("y", 6)
.attr("dy", "0.71em")
.attr("text-anchor", "end")
.text("Price ($)");
g.append("path")
.datum(data)
.attr("fill", "none")
.attr("stroke", "steelblue")
.attr("stroke-linejoin", "round")
.attr("stroke-linecap", "round")
.attr("stroke-width", 1.5)
.attr("d", line);
</script>
But surprisingly, it does not draw the chart. I mean, when I execute the application, there is nothing displayed. I am new to d3.js so referring to sources available on the internet.
What I want to draw is something like in the following.
https://bl.ocks.org/mbostock/3883245
But the data should be taken from the array "data" , not from a file.
Can someoone pls help to figure out what the issue is ?
回答1:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>title</title>
<script src="https://d3js.org/d3.v4.min.js"></script>
<style>
.bar {
fill: steelblue;
}
.bar:hover {
fill: brown;
}
.axis--x path {
display: none;
}
.line {
fill: none;
stroke: steelblue;
stroke-width: 3px;
}
.circle {
fill: steelblue;
}
</style>
</head>
<body>
<svg width="960" height="500"></svg>
<script>
var svg = d3.select("svg"),
margin = {top: 20, right: 20, bottom: 30, left: 40},
width = +svg.attr("width") - margin.left - margin.right,
height = +svg.attr("height") - margin.top - margin.bottom;
var x = d3.scaleBand().rangeRound([0, width]).padding(0.1),
y = d3.scaleLinear().rangeRound([height, 0]);
var g = svg.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")");
var data = [
{ letter: "A", frequency: .08167 },
{ letter: "B", frequency: .01492 },
{ letter: "C", frequency: .02780 },
{ letter: "D", frequency: .04253 },
{ letter: "E", frequency: .12702 },
{ letter: "F", frequency: .02288 },
{ letter: "G", frequency: .02022 },
{ letter: "H", frequency: .06094 },
{ letter: "I", frequency: .06973 },
{ letter: "J", frequency: .00153 },
{ letter: "K", frequency: .00747 },
{ letter: "L", frequency: .04025 },
{ letter: "M", frequency: .02517 },
{ letter: "N", frequency: .06749 },
{ letter: "O", frequency: .07507 },
{ letter: "P", frequency: .01929 },
{ letter: "Q", frequency: .00098 },
{ letter: "R", frequency: .05987 },
{ letter: "S", frequency: .06333 },
{ letter: "T", frequency: .09056 },
{ letter: "U", frequency: .02758 },
{ letter: "V", frequency: .01037 },
{ letter: "W", frequency: .02465 },
{ letter: "X", frequency: .00150 },
{ letter: "Y", frequency: .01971 },
{ letter: "Z", frequency: .00074 }
];
var line = d3.line()
.x(function(d) { return x(d.letter); })
.y(function(d) { return y(d.frequency); })
x.domain(data.map(function(d) { return d.letter; }));
y.domain([0, d3.max(data, function(d) { return d.frequency; })]);
g.append("g")
.attr("class", "axis axis--x")
.attr("transform", "translate(0," + height + ")")
.call(d3.axisBottom(x));
g.append("g")
.attr("class", "axis axis--y")
.call(d3.axisLeft(y).ticks(10, "%"))
.append("text")
.attr("transform", "rotate(-90)")
.attr("y", 6)
.attr("dy", "0.71em")
.attr("text-anchor", "end")
.text("Frequency");
g.append("path")
.datum(data)
.attr("class", "line")
.attr("d", line);
g.selectAll("circle")
.data(data)
.enter().append("circle")
.attr("class", "circle")
.attr("cx", function(d) { return x(d.letter); })
.attr("cy", function(d) { return y(d.frequency); })
.attr("r", 4);
</script>
</body>
</html>
Hope it helps you.
来源：https://stackoverflow.com/questions/45181647/d3-js-line-graph-is-not-displayed