我正在尝试通过块生成器使d3可视化。
我希望Tourdefrance的图片首先出现在整个容器中,然后逐渐消失,然后出现条形图。
我知道通过从各种来源进行复制使我变得有些复杂。
如果有人可以提供帮助并解释问题,那将很好。
<!DOCTYPE html>
<meta charset="utf-8">
<style>
.bar {
fill: steelblue;
}
.bar:hover {
fill: gold;
}
.axis {
font: 10px sans-serif;
}
.axis path,
.axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
.x.axis path {
display: none;
}
</style>
<body>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script>
// Mike Bostock "margin conventions"
var margin = {top: 10, right: 20, bottom: -500, left: 40},
width = 960 - margin.left - margin.right,
height = 500 - margin.top - margin.bottom;
// D3 scales = just math
// x is a function that transforms from "domain" (data) into "range" (usual pixels)
// domain gets set after the data loads
var x = d3.scale.ordinal()
.rangeRoundBands([0, width], .1);
var y = d3.scale.linear()
.range([height, 0]);
// D3 Axis - renders a d3 scale in SVG
var xAxis = d3.svg.axis()
.scale(x)
.orient("bottom");
var yAxis = d3.svg.axis()
.scale(y)
.orient("left")
.ticks(10, "%");
// create an SVG element (appended to body)
// set size
// add a "g" element (think "group")
// annoying d3 gotcha - the 'svg' variable here is a 'g' element
// the final line sets the transform on <g>, not on <svg>
body = d3.select("body");
show_image("https://upload.wikimedia.org/wikipedia/en/e/eb/Tour_de_France_logo.svg")
function show_image(source) {
var img = body.append("img").attr("src", source).style("opacity", 0)
; img.transition().duration(5000).ease(d3.easeLinear).style("opacity", 1)
}
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 + ")");
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
svg.append("g")
.attr("class", "y axis")
.append("text") // just for the title (ticks are automatic)
.attr("transform", "rotate(-90)") // rotate the text!
.attr("y", 6)
.attr("dy", ".71em")
.style("text-anchor", "end")
.text("Frequency");
// d3.tsv is a wrapper around XMLHTTPRequest, returns array of arrays (?) for a TSV file
// type function transforms strings to numbers, dates, etc.
d3.csv("https://gist.githubusercontent.com/vaibhavjaitly/1418c9beb1c71f6acffdaf21669e1956/raw/45af8ebcc87d6641eee8b4a60b7bafb8326607a0/data.csv", type, function(error, data) {
replay(data);
});
function type(d) {
// + coerces to a Number from a String (or anything)
d.Frequency = +d.Frequency;
return d;
}
function replay(data) {
var slices = [];
for (var i = 0; i < data.length; i++) {
slices.push(data.slice(0, i+1));
}
slices.forEach(function(slice, index){
setTimeout(function(){
draw(slice);
}, index * 300);
});
}
function draw(data) {
// measure the domain (for x, unique letters) (for y [0,maxFrequency])
// now the scales are finished and usable
x.domain(data.map(function(d) { return d.Letter; }));
y.domain([0, d3.max(data, function(d) { return d.Frequency; })]);
// another g element, this time to move the origin to the bottom of the svg element
// someSelection.call(thing) is roughly equivalent to thing(someSelection[i])
// for everything in the selection\
// the end result is g populated with text and lines!
svg.select(".x.axis").transition().duration(300).call(xAxis);
// same for yAxis but with more transform and a title
svg.select(".y.axis").transition().duration(300).call(yAxis)
// THIS IS THE ACTUAL WORK!
var bars = svg.selectAll(".bar").data(data, function(d) { return d.Letter; }) // (data) is an array/iterable thing, second argument is an ID generator function
bars.exit()
.transition()
.duration(300)
.attr("y", y(0))
.attr("height", height - y(0))
.style('fill-opacity', 0.00001024)
.remove();
// data that needs DOM = enter() (a set/selection, not an event!)
bars.enter().append("rect")
.attr("class", "bar")
.attr("y", y(0))
.attr("height", height - y(0));
// the "UPDATE" set:
bars.transition().duration(300).attr("x", function(d) { return x(d.Letter); }) // (d) is one item from the data array, x is the scale object from above
.attr("width", x.rangeBand()) // constant, so no callback function(d) here
.attr("y", function(d) { return y(d.Frequency); })
.attr("height", function(d) { return height - y(d.Frequency); }); // flip the height, because y's domain is bottom up, but SVG renders top down
}