Question

我是D3.js的新手我为这里的数据集创建了一个折线图：

Year,NoneFatal,Fatal,Total,FatalPercentage,NoneFatalPercentage
2010,280,116,396,29,71
2011,268,135,403,33,67
2012,267,124,391,32,68
2013,280,111,391,28,72
2014,229,94,323,29,71
2015,231,102,333,31,69
2016,174,79,253,31,69

我打算添加一个简单的互动功能：

在图表中鼠标悬停时，与最近的数据点关联的数据。我想说明致命和非致命枪击的数量以及他们在特定年份的百分比。

这是我用来生成折线图的代码：

<!DOCTYPE html>
<meta charset="utf-8">
<style> /* set the CSS */

.line {
  fill: none;
  stroke: steelblue;
  stroke-width: 2px;
}

</style>
<body>

<!-- load the d3.js library -->     
<script src="https://d3js.org/d3.v4.min.js"></script>
<script>

// set the dimensions and margins of the graph
var margin = {top: 50, right: 50, bottom: 100, left: 80},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

// set the ranges
  var x = d3.scaleTime().range([0, width]);
var y = d3.scaleLinear().range([height, 0]);

  var parseTime = d3.timeParse("%Y");

// define the line
var valueline = d3.line()
    .x(function(d) { return x(d.Year); })
    .y(function(d) { return y(d.Total); });

// append the svg obgect to the body of the page
// appends a 'group' element to 'svg'
// moves the 'group' element to the top left margin
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.csv("fatal_unarmed.csv", function(error, data) {
  if (error) throw error;

  // format the data
  data.forEach(function(d) {
      d.Year = parseTime(d.Year);
      d.Total = +d.Total;
  });

  // Scale the range of the data
  x.domain(d3.extent(data, function(d) { return d.Year}));
  y.domain([0, d3.max(data, function(d) { return d.Total; })]);


  // Add the valueline path.
  svg.append("path")
      .data([data])
      .attr("class", "line")
      .attr("d", valueline);

  // Add the X Axis
  svg.append("g")
      .attr("transform", "translate(0," + height + ")")
      .call(d3.axisBottom(x));

    // text label for the x axis
  svg.append("text")             
      .attr("transform",
            "translate(" + (width/2) + " ," + 
                           (height + margin.top) + ")")
      .style("text-anchor", "middle")
      .text("Year");

  // Add the Y Axis
  svg.append("g")
      .call(d3.axisLeft(y));

    // text label for the y axis
  svg.append("text")
      .attr("transform", "rotate(-90)")
      .attr("y", 0 - margin.left)
      .attr("x",0 - (height / 2))
      .attr("dy", "1em")
      .style("text-anchor", "middle")
      .text("Total Number of Shootings");  

    // Add the scatterplot
  svg.selectAll("dot")
      .data(data)
    .enter().append("circle")
      .attr("r", 5)
      .attr("cx", function(d) { return x(d.Year); })
      .attr("cy", function(d) { return y(d.Total); })
        .style("fill", "steelblue");

});

</script>
</body>

有关如何执行此操作的任何建议吗？

如何在D3中制作折线图

0 个答案: