Javascript 如何在D3龙卷风图中居中Y轴

Javascript 如何在D3龙卷风图中居中Y轴,javascript,d3.js,Javascript,D3.js,我对d3.js完全是个新手,但到目前为止我印象深刻 我被要求创建一个龙卷风图,到目前为止,我已经按照要求完成了几乎所有的工作,但是客户希望Y轴两侧的负X访问是相等的,现在它只是从最高的数据值开始工作 如何确保Y通道的两侧长度相同 这是我的工作代码,如果你加载它,你可以看到第二个图表是非常片面的 <!DOCTYPE html> <meta charset="utf-8"> <style> .bar--positive { fill: #9BCCF5; }

我对d3.js完全是个新手,但到目前为止我印象深刻

我被要求创建一个龙卷风图,到目前为止,我已经按照要求完成了几乎所有的工作,但是客户希望Y轴两侧的负X访问是相等的,现在它只是从最高的数据值开始工作

如何确保Y通道的两侧长度相同

这是我的工作代码,如果你加载它,你可以看到第二个图表是非常片面的

 <!DOCTYPE html>
<meta charset="utf-8">
<style>

.bar--positive {
  fill: #9BCCF5;
}

.bar--negative {
  fill: pink;
}

text {
  font: 10px sans-serif;
}

.axis path,
.axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}
</style>
<body>
<p id="example"></p>
<script src="https://d3js.org/d3.v3.min.js"></script>
<script>

function tornadoChart() {
  var margin = {top: 20, right: 30, bottom: 40, left: 100},
    width = 800 - margin.left - margin.right,
    height = 400 - margin.top - margin.bottom;

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

  var y = d3.scale.ordinal()
      .rangeRoundBands([0, height], 0.1);

  var xAxis = d3.svg.axis()
      .scale(x)
      .orient("bottom")
      .ticks(10)


  var yAxis = d3.svg.axis()
      .scale(y)
      .orient("left")
      .tickSize(0)

  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 + ")");


  function chart(selection) {
    selection.each(function(data) {

      x.domain(d3.extent(data, function(d) { return d.interactions; })).nice();
      y.domain(data.map(function(d) { return d.age; }));

      var minInteractions = Math.max.apply(Math, data.map(function(o){return o.interactions;}))*-1;
      yAxis.tickPadding(Math.abs(x(minInteractions) - x(0)) + 10);

      var bar = svg.selectAll(".bar")
          .data(data)

      bar.enter().append("rect")
          .attr("class", function(d) { return "bar bar--" + (d.interactions < 0 ? "negative" : "positive"); })
          .attr("x", function(d) { return x(Math.min(0, d.interactions)); })
          .attr("y", function(d) { return y(d.age); })
          .attr("width", function(d) { return Math.abs(x(d.interactions) - x(0)); })
          .attr("id", function(d){ return d.age})
          .attr("style", function(d){ return d.colour == null ? "" : "fill:" + d.colour;})
          .attr("height", y.rangeBand())

      bar.enter().append('text')
          .attr("text-anchor", "end")
          .attr("x", function(d,i) {

              var titlePlacement = Math.abs(x(d.interactions) - x(0)) + x(Math.min(0, d.interactions))-5;
              if( Math.abs(x(d.interactions) - x(0)) < 30 && d.interactions > 0)
               titlePlacement += 30;
              else if(d.interactions < 0) //Negative placement
              {
                titlePlacement = x(Math.min(0, d.interactions))-5;

              }


              return titlePlacement;
          })
          .attr("y", function(d,i) {
              return y(d.age) + (y.rangeBand() / 2);
          })
          .attr("dy", ".35em")
          .text(function (d) { return d.interactions; })

      svg.append("g")
          .attr("class", "x axis")
          .attr("transform", "translate(0," + height + ")")
          .call(xAxis);
      svg.append("g")
          .attr("class", "y axis")
          .attr("transform", "translate(" + x(0) + ",0)")
          .call(yAxis);

    });

  }

  return chart;
}



var data = {"MyData":[{"age":"18-24","gender":"male","interactions":21600,"colour":"#ecf"},{"age":"18-24","gender":"female","interactions":-15500,"colour":""},{"age":"25-34","gender":"male","interactions":19500,"colour":"#ecf"},{"age":"25-34","gender":"female","interactions":-5000,"colour":"#ecf"},{"age":"35-44","gender":"male","interactions":10700,"colour":""},{"age":"35-44","gender":"female","interactions":-3500,"colour":"#4264FF"},{"age":"45-54","gender":"male","interactions":5700,"colour":"#ecf"},{"age":"45-54","gender":"female","interactions":-2400,"colour":"#ecf"},{"age":"55-64","gender":"male","interactions":2500,"colour":"#ecf"},{"age":"55-64","gender":"female","interactions":-1100,"colour":"#4264FF"},{"age":"65+","gender":"male","interactions":600,"colour":"#4264FF"},{"age":"65+","gender":"female","interactions":-600,"colour":"#ecf"}],"Other":[{"age":"18-24","gender":"male","interactions":21600},{"age":"18-24","gender":"female","interactions":-5500},{"age":"25-34","gender":"male","interactions":19500},{"age":"25-34","gender":"female","interactions":-5000},{"age":"35-44","gender":"male","interactions":10700},{"age":"35-44","gender":"female","interactions":-3500},{"age":"45-54","gender":"male","interactions":5700},{"age":"45-54","gender":"female","interactions":-2400},{"age":"55-64","gender":"male","interactions":2500},{"age":"55-64","gender":"female","interactions":-1100},{"age":"65+","gender":"male","interactions":600},{"age":"65+","gender":"female","interactions":-600}]};

for (var i in data) {
  var chart = tornadoChart()
  d3.select("#example")
      .datum(data[i])
      .call(chart);
}

</script>
</body>

.bar--正{
填充:#9BCCF5;
}
.bar--负数{
填充:粉红色;
}
正文{
字体:10px无衬线;
}
.轴线路径,
.轴线{
填充:无;
行程:#000;
形状渲染:边缘清晰;
}

函数表(){ var margin={顶部:20,右侧:30,底部:40,左侧:100}, 宽度=800-边距.左-边距.右, 高度=400-margin.top-margin.bottom; var x=d3.scale.linear() .范围([0,宽度]); 变量y=d3.scale.ordinal() .rangeRoundBands([0,高度],0.1); var xAxis=d3.svg.axis() .比例(x) .orient(“底部”) .滴答声(10) var yAxis=d3.svg.axis() .比例(y) .东方(“左”) .1.1尺寸(0) var svg=d3.选择(“正文”).追加(“svg”) .attr(“宽度”,宽度+边距。左侧+边距。右侧) .attr(“高度”,高度+边距。顶部+边距。底部) .附加(“g”) .attr(“转换”、“平移”(+margin.left+)、“+margin.top+”); 功能图(选择){ 选择。每个功能(数据){ x、 domain(d3.extent(数据,函数(d){return d.interactions;})).nice(); y、 域(data.map(函数(d){returnd.age;})); var minInteractions=Math.max.apply(Math,data.map(函数(o){return o.interactions;}))*-1; yAxis.tickPadding(数学abs(x(最小交互)-x(0))+10); var bar=svg.selectAll(“.bar”) .数据(数据) bar.enter().append(“rect”) .attr(“类”,函数(d){return“bar--”+(d.interactions<0?“负”:“正”);}) .attr(“x”,函数(d){return x(Math.min(0,d.interactions));}) .attr(“y”,函数(d){返回y(d.age);}) .attr(“宽度”,函数(d){return Math.abs(x(d.interactions)-x(0));}) .attr(“id”,函数(d){返回d.age}) .attr(“style”,函数(d){返回d.color==null?”:“fill:”+d.color;}) .attr(“高度”,y.rangeBand()) bar.enter().append('text') .attr(“文本锚定”、“结束”) .attr(“x”,函数(d,i){ var titlePlacement=Math.abs(x(d.相互作用)-x(0))+x(Math.min(0,d.相互作用))-5; if(Math.abs(x(d.interactions)-x(0))<30&&d.interactions>0) 滴定位移+=30; else if(d.interactions<0)//负位置 { titlePlacement=x(数学最小值(0,d.interactions))-5; } 返回标题替换; }) .attr(“y”,函数(d,i){ 返回y(d.age)+(y.rangeBand()/2); }) .attr(“dy”,“.35em”) .text(函数(d){return d.interactions;}) svg.append(“g”) .attr(“类”、“x轴”) .attr(“变换”、“平移(0)”、“高度+”) .呼叫(xAxis); svg.append(“g”) .attr(“类”、“y轴”) .attr(“转换”、“平移”(+x(0)+”,0) .呼叫(yAxis); }); } 收益表; } var数据={“MyData”:[{“年龄”:“18-24”,“性别”:“男性”,“互动”:21600,“颜色”:“ecf”},{“年龄”:“18-24”,“性别”:“女性”,“互动”:-15500,“颜色”:“},{“年龄”:“25-34”,“性别”:“男性”,“互动”:19500,“颜色”:“25-34”,“性别”:“女性”,“互动”:-5000”,“颜色”:“年龄”:“35-44”,“性别”:“男性”,“互动”:10700,“颜色”:“}”,“年龄”:“35-44”,“性别”:“女性”,“互动”:-3500,“颜色”:“年龄”:“45-54”,“性别”:“男性”,“互动”:5700,“颜色”:“年龄”:“45-54”,“性别”:“女性”,“互动”:-2400”,“颜色”:“性别”:“男性”,“互动”:2500,“颜色”:“年龄”:“55-64”,“性别”:“女性”:“互动”::-1100,“颜色”:“#4264FF”},{“年龄”:“65+”,“性别”:“男性”,“互动”:600,“颜色”:“#4264FF”},{“年龄”:“65+”,“性别”:“女性”,“互动”:-600,“颜色”:“ecf”},{“年龄”:“18-24”,“性别”:“男性”,“互动”:21600},{“年龄”:“18-24”,“性别”:“女性”,“互动”:-5500},{“年龄”:“25-34”,“性别”:“男性”,“互动”:19500-34},“性别”:“女性”,“互动”:-5000},{“年龄”:“35-44”,“性别”:“男性”,“互动”:-10700},{“年龄”:“35-44”,“性别”:“女性”,“互动”:-3500},{“年龄”:“45-54”,“性别”:“男性”,“互动”:5700},{“年龄”:“45-54”,“性别”:“女性”,“互动”:-2400},{“年龄”:“55-64”,“性别”:“男性”,“互动”:2500},{“年龄”:“55-64”,“性别”:“女性”互动:“-1100},{“年龄”:“65+”,“性别”:“男性”,“互动”:600},{“年龄”:“65+”,“性别”:“女性”,“互动”:-600}]; 用于(数据中的var i){ var chart=tornadoChart() d3.选择(“示例”) .基准(数据[i]) .电话(图表); }
有几种方法可以将y轴定位在中心,这是其中之一:

查找x刻度中的最大绝对值

var maxvalue = (Math.abs(d3.min(data, function(d) {
        return d.interactions; 
    })) > Math.abs(d3.max(data, function(d) { 
        return d.interactions; 
    }))) ? Math.abs(d3.min(data, function(d) {
        return d.interactions; 
    })) : Math.abs(d3.max(data, function(d) {
        return d.interactions; 
    }));
并使用此值设置对称域:

x.domain([maxvalue*-1, maxvalue]);
这是小提琴: