首页 文章

D3:你如何在折线图上突出显示D3的日期范围?

提问于
浏览
1

我正在使用D3构建一个简单的折线图 . 该图表将包含X轴上的一系列日期和Y轴上的一系列值 .

我想在线后画几个矩形 . 这些矩形将跨越图表的高度并跨越我将定义的日期的宽度 . 假设例如,rect 1在Thu 18th到Wed 24th之间,rect 2在Wed 24th到tue 30th之间 .

这些rect也会附加一个click事件 . 因此,如果单击它们,它们将触发我将定义的函数 . 此函数需要知道单击了哪个rect .

以前有人有过这样的经历吗?任何人都可以帮助引导我朝着正确的方向前进吗?非常感谢 .

I've created this Fiddle to get started (based on an mbostock example):

http://jsfiddle.net/Critter/TJqE6/2/

var data = [
  {"date":"1-May-13","close":58.13},
  {"date":"30-Apr-13","close":53.98},
  {"date":"27-Apr-13","close":67.00},
  {"date":"26-Apr-13","close":89.70},
  {"date":"25-Apr-13","close":99.00},
  {"date":"24-Apr-13","close":130.28},
  {"date":"23-Apr-13","close":166.70},
  {"date":"20-Apr-13","close":234.98},
  {"date":"19-Apr-13","close":345.44},
  {"date":"18-Apr-13","close":443.34},
];

var margin = {top: 20, right: 50, bottom: 30, left: 50},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

var parseDate = d3.time.format("%d-%b-%y").parse,
    bisectDate = d3.bisector(function(d) { return d.date; }).left,
    formatValue = d3.format(",.2f"),
    formatCurrency = function(d) { return "$" + formatValue(d); };

var x = d3.time.scale()
    .range([0, width]);

var y = d3.scale.linear()
    .range([height, 0]);

var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom");

var yAxis = d3.svg.axis()
    .scale(y)
    .orient("left");

var line = d3.svg.line()
    .x(function(d) { return x(d.date); })
    .y(function(d) { return y(d.close); });

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 + ")");

  data.forEach(function(d) {
    d.date = parseDate(d.date);
    d.close = +d.close;

  data.sort(function(a, b) {
    return a.date - b.date;
  });

  x.domain([data[0].date, data[data.length - 1].date]);
  y.domain(d3.extent(data, function(d) { return d.close; }));

  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("Price ($)");

  svg.append("path")
      .datum(data)
      .attr("class", "line")
      .attr("d", line);

  var focus = svg.append("g")
      .attr("class", "focus")
      .style("display", "none");

  focus.append("circle")
      .attr("r", 4.5);

  focus.append("text")
      .attr("x", 9)
      .attr("dy", ".35em");

  svg.append("rect")
      .attr("class", "overlay")
      .attr("width", width)
      .attr("height", height)
      .on("mouseover", function() { focus.style("display", null); })
      .on("mouseout", function() { focus.style("display", "none"); })
      .on("mousemove", mousemove);

  function mousemove() {
    var x0 = x.invert(d3.mouse(this)[0]),
        i = bisectDate(data, x0, 1),
        d0 = data[i - 1],
        d1 = data[i],
        d = x0 - d0.date > d1.date - x0 ? d1 : d0;
    focus.attr("transform", "translate(" + x(d.date) + "," + y(d.close) + ")");
    focus.select("text").text(formatCurrency(d.close));
  }
});

1 回答

  • 1

    主要问题是将矩形放在行中 . 给定一个日期,您可以像这样在相应的轴上计算它的位置 - 比如你想在2013年4月19日开始到2013年4月21日结束 .

    //here x is already the x axis time scale you have defined in your code
        var left = x(new Date("Apr 19 2013"));
        var right = x(new Date("Apr 22 2013")); //one more day
        var wid = right - left;
        svg.append("rect")
          .attr("x", left)
          .attr("width", wid)
          .attr("height", height)
    

    现在你也可以添加一个样式类来填充或描边或设置不透明度等 . 添加点击事件应该很容易,但由于SVG没有z-index只依赖于DOM顺序你可以看到你是否可以在你之前插入矩形插入图表线 .

相关问题