Question

我有一个barchart，它使用scaleband()表示x轴上的字母。

有一个刷子可以缩放并平移主图表。但是，使用画笔时，会有一些奇怪的行为。在左角，有一些额外的酒吧在彼此顶部显示。似乎一些不在画笔选择中的条显示尽可能接近x轴原点。对于没有x位置值的条，这必须是默认的x位置。

以下是完整代码：

＆＃13;

<!DOCTYPE html>
<meta charset="utf-8">

<style type="text/css">
  body {
    font-family: avenir next, sans-serif;
    font-size: 12px;
  }

  .zoom {
    cursor: move;
    fill: none;
    pointer-events: all;
  }

  .axis {
    stroke-width: 0.5px;
    stroke: #888;
    font: 10px avenir next, sans-serif;
  }

  .axis>path {
    stroke: #888;
  }
</style>

<body>
</body>

<script src="https://d3js.org/d3.v4.min.js"></script>
<script>
  /* Adapted from: https://bl.ocks.org/mbostock/34f08d5e11952a80609169b7917d4172 */

  var margin = {
      top: 20,
      right: 20,
      bottom: 90,
      left: 50
    },
    margin2 = {
      top: 230,
      right: 20,
      bottom: 30,
      left: 50
    },
    width = 960 - margin.left - margin.right,
    height = 300 - margin.top - margin.bottom,
    height2 = 300 - margin2.top - margin2.bottom;

  var x = d3.scaleBand().rangeRound([0, width]).padding(0.1), //removing rangeRound no effect
    x2 = d3.scaleBand().rangeRound([0, width]).padding(0.1),
    y = d3.scaleLinear().range([height, 0]),
    y2 = d3.scaleLinear().range([height2, 0]);

  var xAxis = d3.axisBottom(x).tickSize(0),
    xAxis2 = d3.axisBottom(x2).tickSize(0),
    yAxis = d3.axisLeft(y).tickSize(0);

  var brush = d3.brushX()
    .extent([
      [0, 0],
      [width, height2]
    ])
    // .on("start brush end", brushed);
    .on("brush", brushed);

  var zoom = d3.zoom()
    .scaleExtent([1, 20])
    .translateExtent([
      [0, 0],
      [width, height]
    ])
    .extent([
      [0, 0],
      [width, height]
    ])
    .on("zoom", zoomed);

  var svg = d3.select("body")
    .append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom);

  svg.append("defs").append("clipPath")
    .attr("id", "clip")
    .append("rect")
    .attr("width", width)
    .attr("height", height);

  var focus = svg.append("g")
    .attr("class", "focus")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

  var context = svg.append("g")
    .attr("class", "context")
    .attr("transform", "translate(" + margin2.left + "," + margin2.top + ")");

  focus.append("text") // yAxis label
    .attr("transform", "rotate(-90)")
    .attr("y", 0 - margin.left)
    .attr("x", 0 - (height / 2))
    .attr("dy", "1em")
    .style("text-anchor", "middle")
    .text("Distance in meters");

  svg.append("text") // xAxis label
    .attr("transform",
      "translate(" + ((width + margin.right + margin.left) / 2) + " ," +
      (height + margin.top + margin.bottom) + ")")
    .style("text-anchor", "middle")
    .text("Date");

  svg.append("rect")
    .attr("class", "zoom")
    .attr("width", width)
    .attr("height", height)
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")")
    .call(zoom); //see var zoom above

  focus.append("g") //append xAxis to main chart
    .attr("class", "axis x-axis")
    .attr("transform", "translate(0," + height + ")")
    .call(xAxis);

  focus.append("g") //append yAxis to main chart
    .attr("class", "axis axis--y")
    .call(yAxis);

  // d3.json("data.json", function(error, data) {
  //   if (error) throw error;
  var data = [{
      "date": "A",
      "distance": "1100"
    },
    {
      "date": "B",
      "distance": "1500"
    },

    {
      "date": "C",
      "distance": "2000"
    },
    {
      "date": "D",
      "distance": "2500"
    },
    {
      "date": "E",
      "distance": "1975"
    },
    {
      "date": "F",
      "distance": "3000"
    },
    {
      "date": "G",
      "distance": "2100"
    },
    {
      "date": "H",
      "distance": "2100"
    },
    {
      "date": "I",
      "distance": "3300"
    },
    {
      "date": "J",
      "distance": "2000"
    },
    {
      "date": "K",
      "distance": "2100"
    },
    {
      "date": "L",
      "distance": "2000"
    },
    {
      "date": "M",
      "distance": "2000"
    },
    {
      "date": "N",
      "distance": "2000"
    },
    {
      "date": "O",
      "distance": "3000"
    },
    {
      "date": "p",
      "distance": "1975"
    },
    {
      "date": "Q",
      "distance": "3000"
    },
    {
      "date": "R",
      "distance": "2100"
    },
    {
      "date": "S",
      "distance": "2100"
    },
    {
      "date": "T",
      "distance": "3300"
    },
    {
      "date": "U",
      "distance": "1500"
    },
    {
      "date": "V",
      "distance": "2100"
    },
    {
      "date": "W",
      "distance": "2000"
    },
    {
      "date": "X",
      "distance": "1800"
    },
    {
      "date": "Y",
      "distance": "2200"
    },
    {
      "date": "Z",
      "distance": "3000"
    }
  ]
  data.forEach(function(d) {
      d.distance = +d.distance;
      return d;
    },
    function(error, data) {
      if (error) throw error;
    });

  x.domain(data.map(function(d) {
    return d.date;
  }));
  y.domain([0, d3.max(data, function(d) {
    return d.distance;
  })]);
  x2.domain(x.domain());
  y2.domain(y.domain());

  //********* Main ar Chart ****************

  var rects = focus.append("g");
  rects.attr("clip-path", "url(#clip)"); //the element to be clipped
  rects.selectAll("rects")
    .data(data)
    .enter().append("rect")
    .style("fill", function(d) {
      return "lightblue";
    })
    .style('stroke', 'gray')
    .attr("class", "rects")
    .attr("x", function(d) {
      return x(d.date);
    })
    .attr("y", function(d) {
      return y(d.distance);
    })
    .attr("width", x.bandwidth())
    .attr("height", function(d) {
      return height - y(d.distance);
    });

  // //********* Brush Bar Chart ****************

  var rects = context.append("g"); //draw bar chart in brush
  rects.attr("clip-path", "url(#clip)");
  rects.selectAll("rect")
    .data(data)
    .enter().append("rect")

    // var focus_group = context.append("g");
    // focus_group.attr("clip-path", "url(#clip)");
    //
    // var brushRects = focus_group.selectAll('rect')
    //   .data(data);
    //
    // //********* Brush Bar Chart ****************
    //
    // var brushRects1 = brushRects.enter();
    //
    // brushRects1.append('rect')

    .style("fill", function(d) {
      return "lightblue";
    })
    .style('stroke', 'gray')
    .attr("class", "rectss")
    .attr("x", function(d) {
      return x2(d.date);
    })
    .attr("y", function(d) {
      return y2(d.distance);
    })
    .attr("width", x.bandwidth())
    .attr("height", function(d) {
      return height2 - y2(d.distance);
    });

  context.append("g")
    .attr("class", "axis x-axis")
    .attr("transform", "translate(0," + height2 + ")")
    .call(xAxis2);

  context.append("g")
    .attr("class", "brush")
    .call(brush)
    .call(brush.move, x.range());
  // });

  //create brush function redraw scatterplot with selection
  function brushed() {
    if (d3.event.sourceEvent && d3.event.sourceEvent.type === "zoom") return; // ignore brush-by-zoom

    // get bounds of selection
    var s = d3.event.selection,
      nD = [];
    x2.domain().forEach((d) => { //not as smooth as I'd like it
      var pos = x2(d) + x2.bandwidth() / 2;
      if (pos > s[0] && pos < s[1]) {
        nD.push(d);
      }
    });

    x.domain(nD);

    // d3.select("rects").remove();

    focus.selectAll(".rects")
      .attr("x", function(d) {
        return x(d.date);
      })
      .attr("y", function(d) {
        return y(d.distance);
      })
      .attr("width", x.bandwidth())
      .attr("height", function(d) {
        return height - y(d.distance);
      });

    focus.select(".x-axis").call(xAxis);

    // var e = d3.event.selection;
    // var selectedrects = focus.selectAll('.rects').filter(function() {
    //   var xValue = this.getAttribute('x');
    //   return e[0] <= xValue && xValue <= e[1];
    // });

    svg.select(".zoom").call(zoom.transform, d3.zoomIdentity
      .scale(width / (s[1] - s[0]))
      .translate(-s[0], 0));
  }

  function zoomed() {}
</script>

＆＃13;

Answer 1

您在图表左侧看到的“奇数”条形图是不在选择范围内的条形图，但仍然显示，因为数据未正确更新*。

根据画笔事件更新数据时，我们需要更新要显示的条形集，并删除不再显示的前一条形。

可以通过以下方式执行画笔更新：

focus.selectAll(".rects")
  // removes previous bars
  .remove().exit()
  // modifies the set of bars to display:
  .data(data.filter( function(d) { return nD.indexOf(d.date) > -1 }))
  .enter().append("rect")
  .style("fill", function(d) {
    return "lightblue";
  })
  .style('stroke', 'gray')
  .attr("class", "rects")
  .attr("x", function(d) {
    return x(d.date);
  })
  ...;

以这种方式移除旧条：

focus.selectAll(".rects").remove().exit()

并且通过过滤原始集合来确定与选择对应的新条形集：

.data(data.filter( function(d) { return nD.indexOf(d.date) > -1 }))

var margin = {
    top: 20,
    right: 20,
    bottom: 90,
    left: 50
  },
  margin2 = {
    top: 230,
    right: 20,
    bottom: 30,
    left: 50
  },
  width = 450 - margin.left - margin.right,
  height = 300 - margin.top - margin.bottom,
  height2 = 300 - margin2.top - margin2.bottom;

var data = [{
    "date": "A",
    "distance": "1100"
  },
  {
    "date": "B",
    "distance": "1500"
  },

  {
    "date": "C",
    "distance": "2000"
  },
  {
    "date": "D",
    "distance": "2500"
  },
  {
    "date": "E",
    "distance": "1975"
  },
  {
    "date": "F",
    "distance": "3000"
  },
  {
    "date": "G",
    "distance": "2100"
  },
  {
    "date": "H",
    "distance": "2100"
  },
  {
    "date": "I",
    "distance": "3300"
  },
  {
    "date": "J",
    "distance": "2000"
  },
  {
    "date": "K",
    "distance": "2100"
  },
  {
    "date": "L",
    "distance": "2000"
  },
  {
    "date": "M",
    "distance": "2000"
  },
  {
    "date": "N",
    "distance": "2000"
  },
  {
    "date": "O",
    "distance": "3000"
  },
  {
    "date": "p",
    "distance": "1975"
  },
  {
    "date": "Q",
    "distance": "3000"
  },
  {
    "date": "R",
    "distance": "2100"
  },
  {
    "date": "S",
    "distance": "2100"
  },
  {
    "date": "T",
    "distance": "3300"
  },
  {
    "date": "U",
    "distance": "1500"
  },
  {
    "date": "V",
    "distance": "2100"
  },
  {
    "date": "W",
    "distance": "2000"
  },
  {
    "date": "X",
    "distance": "1800"
  },
  {
    "date": "Y",
    "distance": "2200"
  },
  {
    "date": "Z",
    "distance": "3000"
  }
]

var x = d3.scaleBand().rangeRound([0, width]).padding(0.1), //removing rangeRound no effect
  x2 = d3.scaleBand().rangeRound([0, width]).padding(0.1),
  y = d3.scaleLinear().range([height, 0]),
  y2 = d3.scaleLinear().range([height2, 0]);

var xAxis = d3.axisBottom(x).tickSize(0),
  xAxis2 = d3.axisBottom(x2).tickSize(0),
  yAxis = d3.axisLeft(y).tickSize(0);

var brush = d3.brushX()
  .extent([
    [0, 0],
    [width, height2]
  ])
  // .on("start brush end", brushed);
  .on("brush", brushed);

var zoom = d3.zoom()
  .scaleExtent([1, 20])
  .translateExtent([
    [0, 0],
    [width, height]
  ])
  .extent([
    [0, 0],
    [width, height]
  ])
  .on("zoom", zoomed);

var svg = d3.select("body")
  .append("svg")
  .attr("width", width + margin.left + margin.right)
  .attr("height", height + margin.top + margin.bottom);

svg.append("defs").append("clipPath")
  .attr("id", "clip")
  .append("rect")
  .attr("width", width)
  .attr("height", height);

var focus = svg.append("g")
  .attr("class", "focus")
  .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

var context = svg.append("g")
  .attr("class", "context")
  .attr("transform", "translate(" + margin2.left + "," + margin2.top + ")");

focus.append("text") // yAxis label
  .attr("transform", "rotate(-90)")
  .attr("y", 0 - margin.left)
  .attr("x", 0 - (height / 2))
  .attr("dy", "1em")
  .style("text-anchor", "middle")
  .text("Distance in meters");

svg.append("text") // xAxis label
  .attr("transform",
    "translate(" + ((width + margin.right + margin.left) / 2) + " ," +
    (height + margin.top + margin.bottom) + ")")
  .style("text-anchor", "middle")
  .text("Date");

svg.append("rect")
  .attr("class", "zoom")
  .attr("width", width)
  .attr("height", height)
  .attr("transform", "translate(" + margin.left + "," + margin.top + ")")
  .call(zoom); //see var zoom above

focus.append("g") //append xAxis to main chart
  .attr("class", "axis x-axis")
  .attr("transform", "translate(0," + height + ")")
  .call(xAxis);

focus.append("g") //append yAxis to main chart
  .attr("class", "axis axis--y")
  .call(d3.axisLeft(d3.scaleLinear().domain([0, d3.max(data, function(d) { return d.distance; })]).range([height, 0])).tickSize(0));


data.forEach(function(d) {
    d.distance = +d.distance;
    return d;
  },
  function(error, data) {
    if (error) throw error;
  });

x.domain(data.map(function(d) {
  return d.date;
}));
y.domain([0, d3.max(data, function(d) {
  return d.distance;
})]);
x2.domain(x.domain());
y2.domain(y.domain());

//********* Main ar Chart ****************

var rects = focus.append("g");
rects.attr("clip-path", "url(#clip)"); //the element to be clipped
rects.selectAll("rects")
  .data(data)
  .enter().append("rect")
  .style("fill", function(d) {
    return "lightblue";
  })
  .style('stroke', 'gray')
  .attr("class", "rects")
  .attr("x", function(d) {
    return x(d.date);
  })
  .attr("y", function(d) {
    return y(d.distance);
  })
  .attr("width", x.bandwidth())
  .attr("height", function(d) {
    return height - y(d.distance);
  });

// //********* Brush Bar Chart ****************

var rects = context.append("g"); //draw bar chart in brush
rects.attr("clip-path", "url(#clip)");
rects.selectAll("rect")
  .data(data)
  .enter().append("rect")

  // var focus_group = context.append("g");
  // focus_group.attr("clip-path", "url(#clip)");
  //
  // var brushRects = focus_group.selectAll('rect')
  //   .data(data);
  //
  // //********* Brush Bar Chart ****************
  //
  // var brushRects1 = brushRects.enter();
  //
  // brushRects1.append('rect')

  .style("fill", function(d) {
    return "lightblue";
  })
  .style('stroke', 'gray')
  .attr("class", "rectss")
  .attr("x", function(d) {
    return x2(d.date);
  })
  .attr("y", function(d) {
    return y2(d.distance);
  })
  .attr("width", x.bandwidth())
  .attr("height", function(d) {
    return height2 - y2(d.distance);
  });

context.append("g")
  .attr("class", "axis x-axis")
  .attr("transform", "translate(0," + height2 + ")")
  .call(xAxis2);

context.append("g")
  .attr("class", "brush")
  .call(brush)
  .call(brush.move, x.range());
// });

//create brush function redraw scatterplot with selection
function brushed() {
  if (d3.event.sourceEvent && d3.event.sourceEvent.type === "zoom") return; // ignore brush-by-zoom

  // get bounds of selection
  var s = d3.event.selection,
    nD = [];
  x2.domain().forEach((d) => { //not as smooth as I'd like it
    var pos = x2(d) + x2.bandwidth() / 2;
    if (pos > s[0] && pos < s[1]) {
      nD.push(d);
    }
  });

  x.domain(nD);

  // d3.select("rects").remove();

  focus.selectAll(".rects")
    .remove().exit()
    .data(data.filter( function(d) { return nD.indexOf(d.date) > -1 }))
    .enter().append("rect")
    .style("fill", function(d) {
      return "lightblue";
    })
    .style('stroke', 'gray')
    .attr("class", "rects")
    .attr("x", function(d) {
      return x(d.date);
    })
    .attr("y", function(d) {
      return y(d.distance);
    })
    .attr("width", x.bandwidth())
    .attr("height", function(d) {
      return height - y(d.distance);
    });

  focus.select(".x-axis").call(xAxis);

  // var e = d3.event.selection;
  // var selectedrects = focus.selectAll('.rects').filter(function() {
  //   var xValue = this.getAttribute('x');
  //   return e[0] <= xValue && xValue <= e[1];
  // });

  svg.select(".zoom").call(zoom.transform, d3.zoomIdentity
    .scale(width / (s[1] - s[0]))
    .translate(-s[0], 0));
}

function zoomed() {}

body {
  font-family: avenir next, sans-serif;
  font-size: 12px;
}

.zoom {
  cursor: move;
  fill: none;
  pointer-events: all;
}

.axis {
  stroke-width: 0.5px;
  stroke: #888;
  font: 10px avenir next, sans-serif;
}

.axis>path {
  stroke: #888;
}

<!DOCTYPE html>
<meta charset="utf-8">

<body></body>

<script src="https://d3js.org/d3.v4.min.js"></script>

_{*：当通过新的x计算其关联的x.domain位置时，不再属于该范围的条形成为undefined，其被解释为{{ 1}}。这就是它们显示在图表左侧的原因。}

条形图条形图使用画笔聚集起来

1 个答案: