我的数据如下:
var chartData = [[9.402974983096687, "Asian"], [10.762177012177013, "Black"], [12.213470319634704, "Chinese"], [11.211221431247658, "Hispanic"], [9.18421052631579, "American Indian"], [12.36144578313253, "Japanese"], [14.659334126040427, "Other"], [7.5, "Portuguese"], [10.636304446904095, "White"]];
我正在尝试将其转换为格式:
[
{
"Ethinicity": "Asian",
"Facebook_usage": 9.40
},
{
"Ethinicity" : "Black",
"Freq": 12.213470319634704
},
{
"Ethinicity":"Chinese"
"Freq": 12.213470319634704
},
----]
然后,从中制作条形图。使用map函数尝试如下:
chartData.map(function(e, i) {
facebook_usage.push(e[0]);
ethinicity.push(e[1]);
}
var chartData = create_JSON(facebook_usage,ethinicity) {
--not sure how to frame this function }
以下是绘制条形图的其余代码:
var margin = {top: 20, right: 20, bottom: 70, left: 40},
width = 600 - margin.left - margin.right,
height = 300 - margin.top - margin.bottom;
// set the ranges
var x = d3.scale.ordinal().rangeRoundBands([0, width], .05);
var y = d3.scale.linear().range([height, 0]);
// define the axis
var xAxis = d3.svg.axis()
.scale(x)
.orient("bottom")
var yAxis = d3.svg.axis()
.scale(y)
.orient("left")
.ticks(10);
// add the SVG element
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 + ")");
// load the data
chartData.forEach(function(d) {
d.ethinicity = d.ethinicity;
d.facebook_usage = d.facebook_usage;
});
// scale the range of the data
x.domain(data.map(function(d) { return d.ethinicity; }));
y.domain([0, d3.max(data, function(d) { return d.facebook_usage; })]);
// add axis
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis)
.selectAll("text")
.style("text-anchor", "end")
.attr("dx", "-.8em")
.attr("dy", "-.55em")
.attr("transform", "rotate(-90)" );
svg.append("g")
.attr("class", "y axis")
.call(yAxis)
.append("text")
.attr("transform", "rotate(-90)")
.attr("y", 5)
.attr("dy", ".71em")
.style("text-anchor", "end")
.text("Frequency");
// Add bar chart
svg.selectAll("bar")
.data(chartData)
.enter().append("rect")
.attr("class", "bar")
.attr("x", function(d) { return x(d.ethinicity); })
.attr("width", x.rangeBand())
.attr("y", function(d) { return y(d.facebook_usage); })
.attr("height", function(d) { return height - y(d.facebook_usage); });
仍在努力寻找d3.js的方法。以下是fiddle
答案 0 :(得分:2)
您的代码现在有几个问题。
您在设置x和y域时使用变量data
。但是,该变量未在任何地方定义,这就是未生成图表的原因。
您正在定义2个数组,并尝试两次进行数据映射。您可以删除第一步。执行以下操作就足够了。
// directly map your data
chartData.forEach(function(d) {
d.ethinicity = d[1];
d.facebook_usage = +d[0];
});
检查下面的嵌入式代码段。
P.S。你的x轴定位关闭,你可能想调整它。
var chartData = [
[9.402974983096687, "Asian"],
[10.762177012177013, "Black"],
[12.213470319634704, "Chinese"],
[11.211221431247658, "Hispanic"],
[9.18421052631579, "American Indian"],
[12.36144578313253, "Japanese"],
[14.659334126040427, "Other"],
[7.5, "Portuguese"],
[10.636304446904095, "White"]
];
// No need to do the below
/*
var facebook_usage = [];
var ethinicity = [];
chartData.map(function(e, i) {
facebook_usage.push(e[0]);
ethinicity.push(e[1]);
});
//console.log(chartData);
*/
var margin = {
top: 20,
right: 20,
bottom: 70,
left: 40
},
width = 600 - margin.left - margin.right,
height = 300 - margin.top - margin.bottom;
// set the ranges
var x = d3.scale.ordinal().rangeRoundBands([0, width], .05);
var y = d3.scale.linear().range([height, 0]);
// define the axis
var xAxis = d3.svg.axis()
.scale(x)
.orient("bottom")
var yAxis = d3.svg.axis()
.scale(y)
.orient("left")
.ticks(10);
// add the SVG element
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 + ")");
// load the data
// directly map your data here
chartData.forEach(function(d) {
d.ethinicity = d[1];
d.facebook_usage = +d[0];
});
//console.log(chartData);
// scale the range of the data
x.domain(chartData.map(function(d) {
return d.ethinicity;
}));
y.domain([0, d3.max(chartData, function(d) {
return d.facebook_usage;
})]);
// add axis
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis)
.selectAll("text")
.style("text-anchor", "end")
.attr("dx", "-.8em")
.attr("dy", "-.55em")
.attr("translate", "rotate(-90)");
svg.append("g")
.attr("class", "y axis")
.call(yAxis)
.append("text")
.attr("transform", "rotate(-90)")
.attr("y", 5)
.attr("dy", ".71em")
.style("text-anchor", "end")
.text("Frequency");
// Add bar chart
svg.selectAll("bar")
.data(chartData)
.enter().append("rect")
.attr("class", "bar")
.attr("x", function(d) {
return x(d.ethinicity);
})
.attr("width", x.rangeBand())
.attr("y", function(d) {
return y(d.facebook_usage);
})
.attr("height", function(d) {
return height - y(d.facebook_usage);
});

.bar {
fill: steelblue;
}
.bar:hover {
fill: brown;
}
.axis {
font: 10px sans-serif;
}
.axis path,
.axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
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