javascript - D3 条形图中第一个条之前不需要的空格

Question

我正在尝试将数据集填充到 D3 的条形图数据中。我正在使用 d3 中的这个示例:http://bl.ocks.org/mbostock/3885304

这是我的示例数据:

var data = [{"name":"0","members_count":4},{"name":"1","members_count":1},{"name":"2","members_count":6},{"name":"3","members_count":1},{"name":"4","members_count":1},{"name":"5","members_count":2},{"name":"6","members_count":4},{"name":"7","members_count":3},{"name":"8","members_count":5},{"name":"9","members_count":1},{"name":"10","members_count":2},{"name":"11","members_count":3},{"name":"12","members_count":2},{"name":"13","members_count":0},{"name":"14","members_count":5},{"name":"15","members_count":2},{"name":"16","members_count":2},{"name":"17","members_count":4},{"name":"18","members_count":2},{"name":"19","members_count":4},{"name":"20","members_count":3},{"name":"21","members_count":5},{"name":"22","members_count":8},{"name":"23","members_count":3},{"name":"24","members_count":2},{"name":"25","members_count":3},{"name":"26","members_count":4},{"name":"27","members_count":4},{"name":"28","members_count":1},{"name":"29","members_count":1},{"name":"30","members_count":3},{"name":"31","members_count":5},{"name":"32","members_count":4},{"name":"33","members_count":3},{"name":"34","members_count":6},{"name":"35","members_count":2},{"name":"36","members_count":2},{"name":"37","members_count":7},{"name":"38","members_count":2},{"name":"39","members_count":4},{"name":"40","members_count":2},{"name":"41","members_count":1},{"name":"42","members_count":8},{"name":"43","members_count":10},{"name":"44","members_count":1},{"name":"45","members_count":5},{"name":"46","members_count":2},{"name":"47","members_count":5},{"name":"48","members_count":3},{"name":"49","members_count":1},{"name":"50","members_count":9},{"name":"51","members_count":3},{"name":"52","members_count":2},{"name":"53","members_count":8},{"name":"54","members_count":2},{"name":"55","members_count":3},{"name":"56","members_count":2},{"name":"57","members_count":2},{"name":"58","members_count":5},{"name":"59","members_count":1},{"name":"60","members_count":2},{"name":"61","members_count":4},{"name":"62","members_count":2},{"name":"63","members_count":2},{"name":"64","members_count":6},{"name":"65","members_count":6},{"name":"66","members_count":1},{"name":"67","members_count":1},{"name":"68","members_count":3},{"name":"69","members_count":5},{"name":"70","members_count":3},{"name":"71","members_count":4},{"name":"72","members_count":4},{"name":"73","members_count":1},{"name":"74","members_count":3},{"name":"75","members_count":2},{"name":"76","members_count":4},{"name":"77","members_count":5},{"name":"78","members_count":2},{"name":"79","members_count":1},{"name":"80","members_count":2},{"name":"81","members_count":1},{"name":"82","members_count":4},{"name":"83","members_count":3},{"name":"84","members_count":1},{"name":"85","members_count":4},{"name":"86","members_count":1},{"name":"87","members_count":3},{"name":"88","members_count":1},{"name":"89","members_count":8},{"name":"90","members_count":6},{"name":"91","members_count":6},{"name":"92","members_count":3},{"name":"93","members_count":4},{"name":"94","members_count":5},{"name":"95","members_count":2},{"name":"96","members_count":3},{"name":"97","members_count":2},{"name":"98","members_count":3},{"name":"99","members_count":6},{"name":"100","members_count":3},{"name":"101","members_count":1},{"name":"102","members_count":0},{"name":"103","members_count":5},{"name":"104","members_count":2},{"name":"105","members_count":1},{"name":"106","members_count":7},{"name":"107","members_count":1},{"name":"108","members_count":1},{"name":"109","members_count":7},{"name":"110","members_count":5},{"name":"111","members_count":5},{"name":"112","members_count":2},{"name":"113","members_count":6},{"name":"114","members_count":1},{"name":"115","members_count":2},{"name":"116","members_count":1},{"name":"117","members_count":1},{"name":"118","members_count":10},{"name":"119","members_count":2},{"name":"120","members_count":6},{"name":"121","members_count":1},{"name":"122","members_count":1},{"name":"123","members_count":2},{"name":"124","members_count":4},{"name":"125","members_count":5},{"name":"126","members_count":1},{"name":"127","members_count":1},{"name":"128","members_count":1},{"name":"129","members_count":3},{"name":"130","members_count":3},{"name":"131","members_count":3},{"name":"132","members_count":4},{"name":"133","members_count":3},{"name":"134","members_count":1},{"name":"135","members_count":5},{"name":"136","members_count":5},{"name":"137","members_count":1},{"name":"138","members_count":2},{"name":"139","members_count":5},{"name":"140","members_count":1},{"name":"141","members_count":1},{"name":"142","members_count":2},{"name":"143","members_count":2},{"name":"144","members_count":4},{"name":"145","members_count":4},{"name":"146","members_count":3},{"name":"147","members_count":5},{"name":"148","members_count":2},{"name":"149","members_count":1},{"name":"150","members_count":2},{"name":"151","members_count":3},{"name":"152","members_count":0},{"name":"153","members_count":3},{"name":"154","members_count":1},{"name":"155","members_count":2},{"name":"156","members_count":2},{"name":"157","members_count":1},{"name":"158","members_count":5},{"name":"159","members_count":4},{"name":"160","members_count":4},{"name":"161","members_count":5},{"name":"162","members_count":4},{"name":"163","members_count":2},{"name":"164","members_count":4},{"name":"165","members_count":2},{"name":"166","members_count":2},{"name":"167","members_count":1},{"name":"168","members_count":1},{"name":"169","members_count":10},{"name":"170","members_count":4},{"name":"171","members_count":2},{"name":"172","members_count":2},{"name":"173","members_count":1},{"name":"174","members_count":5},{"name":"175","members_count":1},{"name":"176","members_count":1},{"name":"177","members_count":5},{"name":"178","members_count":3},{"name":"179","members_count":1},{"name":"180","members_count":5},{"name":"181","members_count":8},{"name":"182","members_count":4},{"name":"183","members_count":2},{"name":"184","members_count":1},{"name":"185","members_count":3},{"name":"186","members_count":1},{"name":"187","members_count":3},{"name":"188","members_count":1},{"name":"189","members_count":1},{"name":"190","members_count":6},{"name":"191","members_count":4},{"name":"192","members_count":5},{"name":"193","members_count":1},{"name":"194","members_count":4},{"name":"195","members_count":2},{"name":"196","members_count":2},{"name":"197","members_count":2},{"name":"198","members_count":0},{"name":"199","members_count":3},{"name":"200","members_count":3},{"name":"201","members_count":1},{"name":"202","members_count":1},{"name":"203","members_count":1},{"name":"204","members_count":5},{"name":"205","members_count":1},{"name":"206","members_count":1},{"name":"207","members_count":1},{"name":"208","members_count":1},{"name":"209","members_count":1},{"name":"210","members_count":5},{"name":"211","members_count":2},{"name":"212","members_count":1},{"name":"213","members_count":5},{"name":"214","members_count":1},{"name":"215","members_count":3},{"name":"216","members_count":1},{"name":"217","members_count":1},{"name":"218","members_count":4},{"name":"219","members_count":2},{"name":"220","members_count":1},{"name":"221","members_count":3},{"name":"222","members_count":1},{"name":"223","members_count":3},{"name":"224","members_count":1},{"name":"225","members_count":2},{"name":"226","members_count":1},{"name":"227","members_count":1},{"name":"228","members_count":11},{"name":"229","members_count":9},{"name":"230","members_count":9},{"name":"231","members_count":9},{"name":"232","members_count":10},{"name":"233","members_count":10},{"name":"234","members_count":10},{"name":"235","members_count":9},{"name":"236","members_count":10},{"name":"237","members_count":10},{"name":"238","members_count":10},{"name":"239","members_count":10},{"name":"240","members_count":9},{"name":"241","members_count":9},{"name":"242","members_count":9},{"name":"243","members_count":10},{"name":"244","members_count":10},{"name":"245","members_count":9},{"name":"246","members_count":2},{"name":"247","members_count":1},{"name":"248","members_count":2},{"name":"249","members_count":2},{"name":"250","members_count":1},{"name":"251","members_count":2},{"name":"252","members_count":1},{"name":"253","members_count":5},{"name":"254","members_count":1},{"name":"255","members_count":1},{"name":"256","members_count":1},{"name":"257","members_count":1},{"name":"258","members_count":1},{"name":"259","members_count":1},{"name":"260","members_count":2},{"name":"261","members_count":1},{"name":"262","members_count":1},{"name":"263","members_count":2},{"name":"264","members_count":1},{"name":"265","members_count":1},{"name":"266","members_count":1},{"name":"267","members_count":1},{"name":"268","members_count":2},{"name":"269","members_count":2},{"name":"270","members_count":1},{"name":"271","members_count":1},{"name":"272","members_count":0},{"name":"273","members_count":2},{"name":"274","members_count":1},{"name":"275","members_count":2},{"name":"276","members_count":2},{"name":"277","members_count":1},{"name":"278","members_count":3},{"name":"279","members_count":1},{"name":"280","members_count":1},{"name":"281","members_count":1},{"name":"282","members_count":1},{"name":"283","members_count":1},{"name":"284","members_count":1},{"name":"285","members_count":1},{"name":"286","members_count":1},{"name":"287","members_count":1},{"name":"288","members_count":1},{"name":"289","members_count":1},{"name":"290","members_count":1},{"name":"291","members_count":1},{"name":"292","members_count":1},{"name":"293","members_count":1},{"name":"294","members_count":1},{"name":"295","members_count":1},{"name":"296","members_count":1},{"name":"297","members_count":2},{"name":"298","members_count":2},{"name":"299","members_count":1},{"name":"300","members_count":1},{"name":"301","members_count":1},{"name":"302","members_count":1},{"name":"303","members_count":1},{"name":"304","members_count":1},{"name":"305","members_count":1},{"name":"306","members_count":1},{"name":"307","members_count":1},{"name":"308","members_count":1},{"name":"309","members_count":1},{"name":"310","members_count":1},{"name":"311","members_count":1},{"name":"312","members_count":1},{"name":"313","members_count":0},{"name":"314","members_count":1}]

这是图表的绘制代码。

var margin = {top: 20, right: 20, bottom: 30, left: 40},
        width = (960 - margin.left - margin.right) * data.length/50,
        height = 500 - margin.top - margin.bottom;

    var x = d3.scale.ordinal()
        .domain([0,1])
        .rangeRoundBands([0, width], 0.1);

    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")
        .ticks(10, "%");

    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 + ")");
      x.domain(data.map(function(d) { return d.name; }));
      y.domain([0, d3.max(data, function(d) { return d.members_count; })]);

      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("Frequency");

      svg.selectAll(".bar")
          .data(data)
        .enter().append("rect")
          .attr("class", "bar")
          .attr("fill","green")
          .attr("x", function(d) { return x(d.name); })
          .attr("width", x.rangeBand())
          .attr("y", function(d) { return y(d.members_count); })
          .attr("height", function(d) { return height - y(d.members_count); });

我遇到的这个问题是我有一些看起来很难看的空白。此空间位于图表的第一个柱之前和最后一个柱之后。我试过调整条形的 x 值，但我认为这不是一个好方法。

当数据集很小的时候，这个空间就不会来了。但是当数据集很大时，这个空间就会出现。如何从开头和结尾删除这个空格。

Answer 1

问题在于这条线的比例:

.rangeRoundBands([0, width], 0.1);

当没有指定第三个参数 outerPadding 时，它会在图表前后添加 padding 参数为每​​个柱产生的额外空间。您已将 padding 设置为 0.1。要解决此问题，请设置 outerPadding 参数:

var x = d3.scale.ordinal()
    .domain([0,1])
    .rangeRoundBands([0, width], 0.1, 0);

此处更新了您的代码:http://jsfiddle.net/ojntup1a/