如何在d3.js图中转换多行？
问题描述：
我一直在尝试改编Mike Bostock的chained transition script来处理多条线路，但我没有得到它的工作。第一次显示后，线条和标签飞出了阴谋，不再显示了所有事情都得到了更新（我可以看到在检查JavaScript控制台时，线条的值会发生变化）。我不明白我做错了什么。我将在下面发布（冗长的）代码（对长度表示歉意）。我将不胜感激任何帮助，谢谢！如何在d3.js图中转换多行？
<!DOCTYPE html>
<head>
<title>Modified Chained Transitions</title>
<meta charset="utf-8">
<script src="https://d3js.org/d3.v3.min.js"></script>
<style>
body {
font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
margin: auto;
position: relative;
width: 960px;
}
text {
font: 10px sans-serif;
}
.axis path,
.axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
.x.axis path {
display: none;
}
.line {
fill: none;
stroke: steelblue;
stroke-width: 1.5px;
}
form {
position: absolute;
right: 10px;
top: 10px;
}
</style>
</head>
<body>
<br>
<button type="button"> Request data</button>
<div id='chart'> </div>
</body>
<script>
var margin = {top: 20, right: 80, bottom: 30, left: 50},
width = 750 - margin.left - margin.right,
height = 500 - margin.top - margin.bottom;
var parseDate = d3.time.format("%Y%m%d").parse;
var xScale = d3.time.scale()
.range([0, width]);
var yScale = d3.scale.linear()
.range([height, 0]);
var color = d3.scale.category10();
var xAxis = d3.svg.axis()
.scale(xScale)
.orient("bottom");
var yAxis = d3.svg.axis()
.scale(yScale)
.orient("left");
var line = d3.svg.line()
.interpolate("basis")
.x(function(d) { return xScale(d.date); })
.y(function(d) { return yScale(d.temperature); });
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 getNewData = function() {
var data = [];
var counter = 0;
function generate(){
var startDate = new Date;
counter += 1;
var range = counter % 2 === 0 ? 10 : 100;
for (i = 0; i < 100; i++) {
data[i] = {"date": new Date(startDate - i),
"New York": Math.random() * (range - 1),
"San Francisco": Math.random() * (range - 1),
"Austin": Math.random() * (range - 10)};
}
return data;
}
return {
new: function() {return generate()}
};
}; // function getNewData()
var newData = getNewData();
data = newData.new();
color.domain(d3.keys(data[0]).filter(function(key) { return key !== "date"; }));
var cities = color.domain().map(function(name) {
return {
name: name,
values: data.map(function(d) {
return { date: d.date, temperature: +d[name]};
})
};
});
xScale.domain(d3.extent(data, function(d) { return d.date; }));
yScale.domain([
d3.min(cities, function(c) {
return d3.min(c.values, function(v) { return v.temperature; }); }),
d3.max(cities, function(c) {
return d3.max(c.values, function(v) { return v.temperature; }); })
]);
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
svg.append("g")
.attr("class", "y axis")
.call(yAxis)
.append("text")
.attr("transform", "rotate(-90)")
.attr("y", 6)
.attr("dy", ".71em")
.style("text-anchor", "end")
.text("Temperature (ºF)");
var city = svg.selectAll(".city")
.data(cities)
.enter().append("g")
.attr("class", "city");
city.append("path")
.attr("class", "line")
.attr("d", function(d) { return line(d.values); })
.style("stroke", function(d) { return color(d.name); });
city.append("text")
.datum(function(d) { return {name: d.name, values: d.values[0]}; })
.attr("class", "label")
.attr("transform", function(d) { return "translate(" +
xScale(d.values.date) + "," + yScale(d.values.temperature) + ")"; })
.attr("x", 3)
.attr("dy", ".35em")
.text(function(d) { return d.name; });
d3.selectAll("button").on("click", change);
function change() {
data = newData.new();
color.domain(d3.keys(data[0]).filter(function(key) { return key !== "date"; }));
cities = color.domain().map(function(name) {
return {
name: name,
values: data.map(function(d) {
return { date: d.date, temperature: +d[name]};
})
};
});
console.log(cities[0].values[0]);
xScale.domain(d3.extent(data, function(d) { return d.date; }));
yScale.domain([
d3.min(cities, function(c) {
return d3.min(c.values, function(v) { return v.temperature; }); }),
d3.max(cities, function(c) {
return d3.max(c.values, function(v) { return v.temperature; }); })
]);
var t0 = svg.transition().duration(750);
t0.selectAll(".line")
.attr("d", function(cities) { return line(cities.values); })
.style("stroke", function(cities) { return color(cities.name); });
t0.selectAll(".label").attr("transform",
"translate(0,0)").text(function(cities) { return cities.name; });
var t1 = t0.transition();
// t1.selectAll(".line").attr("d", line(data));
// t1.select(".line")
t1.selectAll(".line")
// t1.selectAll(".city")
.attr("d", function(cities) { return line(cities.values); })
.style("stroke", function(cities) { return color(cities.name); });
t1.select(".y.axis").call(yAxis);
t1.select(".x.axis").call(xAxis);
t1.select(".label")
.attr("transform", function(d) { return "translate(" +
xScale(d.values.date) + "," +
yScale(d.values.temperature) + ")"; });
} // function change()
</script>
</html>
答
我可以帮助修复您的转换，但我不确定您试图“链接”。在链接的例子中，Bostock将一行换成另一行（转换1），然后将该行适配到新的域（转换2）。你似乎不想交换线，所以你适合一个新的领域，然后过渡线（过渡1），但什么是过渡2？
现在要回答你更直接的问题，说明为什么你的转换不起作用，这只是因为你永远不会更新你的数据。在链接的例子中，Bostock将数据集绑定到他的行，然后交换他在行函数中绘制的数据集。但是，您只能拥有原始数据集。快速修复是：
function change() {
... //<-- get new data
// bind your new data
var cities = svg.selectAll(".city")
.data(cities)
// sub selection to transition line
cities
.select(".line")
.transition()
.duration(750)
.attr("d", function(d) { return line(d.values); })
.style("stroke", function(d) { return color(d.name); })
// concurrent sub selection to move labels
cities
.select(".label")
.transition()
.duration(750)
.attr("transform", function(d){
var last = d.values[0];
return "translate(" + xScale(last.date) + "," + yScale(last.temperature) + ")";
})
}
运行代码：
<!DOCTYPE html>
<head>
<title>Modified Chained Transitions</title>
<meta charset="utf-8">
<script src="https://d3js.org/d3.v3.min.js"></script>
<style>
body {
font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
margin: auto;
position: relative;
width: 960px;
}
text {
font: 10px sans-serif;
}
.axis path,
.axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
.x.axis path {
display: none;
}
.line {
fill: none;
stroke: steelblue;
stroke-width: 1.5px;
}
form {
position: absolute;
right: 10px;
top: 10px;
}
</style>
</head>
<body>
<br>
<button type="button"> Request data</button>
<div id='chart'> </div>
</body>
<script>
var margin = {
top: 20,
right: 80,
bottom: 30,
left: 50
},
width = 500 - margin.left - margin.right,
height = 500 - margin.top - margin.bottom;
var parseDate = d3.time.format("%Y%m%d").parse;
var xScale = d3.time.scale()
.range([0, width]);
var yScale = d3.scale.linear()
.range([height, 0]);
var color = d3.scale.category10();
var xAxis = d3.svg.axis()
.scale(xScale)
.orient("bottom");
var yAxis = d3.svg.axis()
.scale(yScale)
.orient("left");
var line = d3.svg.line()
.interpolate("basis")
.x(function(d) {
return xScale(d.date);
})
.y(function(d) {
return yScale(d.temperature);
});
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 getNewData = function() {
var data = [];
var counter = 0;
function generate() {
var startDate = new Date;
counter += 1;
var range = counter % 2 === 0 ? 10 : 100;
for (i = 0; i < 100; i++) {
data[i] = {
"date": new Date(startDate - i),
"New York": Math.random() * (range - 1),
"San Francisco": Math.random() * (range - 1),
"Austin": Math.random() * (range - 10)
};
}
return data;
}
return {
new: function() {
return generate()
}
};
}; // function getNewData()
var newData = getNewData();
data = newData.new();
color.domain(d3.keys(data[0]).filter(function(key) {
return key !== "date";
}));
var cities = color.domain().map(function(name) {
return {
name: name,
values: data.map(function(d) {
return {
date: d.date,
temperature: +d[name]
};
})
};
});
xScale.domain(d3.extent(data, function(d) {
return d.date;
}));
yScale.domain([
d3.min(cities, function(c) {
return d3.min(c.values, function(v) {
return v.temperature;
});
}),
d3.max(cities, function(c) {
return d3.max(c.values, function(v) {
return v.temperature;
});
})
]);
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
svg.append("g")
.attr("class", "y axis")
.call(yAxis)
.append("text")
.attr("transform", "rotate(-90)")
.attr("y", 6)
.attr("dy", ".71em")
.style("text-anchor", "end")
.text("Temperature (ºF)");
var city = svg.selectAll(".city")
.data(cities)
.enter().append("g")
.attr("class", "city");
city.append("path")
.attr("class", "line")
.attr("d", function(d) {
return line(d.values);
})
.style("stroke", function(d) {
return color(d.name);
});
city.append("text")
.datum(function(d) {
return {
name: d.name,
values: d.values[0]
};
})
.attr("class", "label")
.attr("transform", function(d) {
return "translate(" +
xScale(d.values.date) + "," + yScale(d.values.temperature) + ")";
})
.attr("x", 3)
.attr("dy", ".35em")
.text(function(d) {
return d.name;
});
d3.selectAll("button").on("click", change);
function change() {
data = newData.new();
color.domain(d3.keys(data[0]).filter(function(key) {
return key !== "date";
}));
cities = color.domain().map(function(name) {
return {
name: name,
values: data.map(function(d) {
return {
date: d.date,
temperature: +d[name]
};
})
};
});
xScale.domain(d3.extent(data, function(d) {
return d.date;
}));
yScale.domain([
d3.min(cities, function(c) {
return d3.min(c.values, function(v) {
return v.temperature;
});
}),
d3.max(cities, function(c) {
return d3.max(c.values, function(v) {
return v.temperature;
});
})
]);
var cities = svg.selectAll(".city")
.data(cities)
cities
.select(".line")
.transition()
.duration(750)
.attr("d", function(d) {
return line(d.values);
})
.style("stroke", function(d) {
return color(d.name);
})
cities
.select(".label")
.transition()
.duration(750)
.attr("transform", function(d) {
var last = d.values[0];
return "translate(" + xScale(last.date) + "," + yScale(last.temperature) + ")";
})
svg.selectAll(".y.axis")
.transition()
.duration(750)
.call(yAxis);
svg.selectAll(".x.axis")
.transition()
.duration(750)
.call(xAxis);
} // function change()
</script>
</html>