javascript - 将 x 轴与零刻度 d3 条形图对齐

我有一个显示正值和负值的条形图。有没有办法让 x 轴与零值同步？此外，x 轴上的刻度似乎不限于指定的 5。有没有办法解决这些问题？

var xAxis = d3.axisBottom()
    .scale(x)
    .tickFormat(d3.timeFormat("%b %Y"))
    .ticks(5);

这是包含代码的 fiddle

https://jsfiddle.net/umshqLyj/3/

最佳答案

使用您的 y 比例来平移轴:

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

这是带有该更改的代码:

var margin = {
    top: 20,
    right: 20,
    bottom: 70,
    left: 40
  },
  width = 600 - margin.left - margin.right,
  height = 300 - margin.top - margin.bottom;
// Parse the date / time
var parseDate = d3.isoParse;
var x = d3.scaleBand().rangeRound([0, width], .05).padding(0.1);
var y = d3.scaleLinear().range([height, 0]);
var xAxis = d3.axisBottom()
  .scale(x)
  .tickFormat(d3.timeFormat("%b %Y"))
  .ticks(5);
var yAxis = d3.axisLeft()
  .scale(y)
  .ticks(5);
var svg = d3.select("body").append("svg")
  .attr("width", width + margin.left + margin.right)
  .attr("height", height + margin.top + margin.bottom)
var g = svg.append("g")
  .attr("transform",
    "translate(" + margin.left + "," + margin.top + ")");
var data = [{
  date: '2016-03-02T00:00:00-05:00',
  value: 5
}, {
  date: '2016-04-03T00:00:00-05:00',
  value: 1
}, {
  date: '2016-05-04T00:00:00-05:00',
  value: -2
}, {
  date: '2016-06-05T00:00:00-05:00',
  value: 3
}, {
  date: '2016-07-06T00:00:00-05:00',
  value: 3
}, {
  date: '2016-08-07T00:00:00-05:00',
  value: 4
}, {
  date: '2016-09-08T00:00:00-05:00',
  value: 4
}, {
  date: '2016-11-09T00:00:00-05:00',
  value: 4
}, {
  date: '2016-12-10T00:00:00-05:00',
  value: -3
}, {
  date: '2017-01-11T00:00:00-05:00',
  value: 5
}, {
  date: '2017-02-12T00:00:00-05:00',
  value: 3
}, {
  date: '2017-03-13T00:00:00-05:00',
  value: -4
}, {
  date: '2017-04-14T00:00:00-05:00',
  value: 2
}, {
  date: '2017-05-15T00:00:00-05:00',
  value: 4
}];
data.forEach(function(d) {
  d.date = parseDate(d.date);
  d.value = +d.value;
});
x.domain(data.map(function(d) {
  return d.date;
}));
y.domain([-5, 5]);
g.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("Value");
g.selectAll(".bar")
  .data(data)
  .enter().append("rect")
  .attr("class", function(d) {
    if (d.value > 0) {
      return 'bar blue';
    } else {
      return 'bar red';
    }
  })
  .attr("x", function(d) {
    return x(d.date);
  })
  .attr("width", x.bandwidth())
  .attr("y", function(d) {
    return y(Math.max(0, d.value));
  })
  .attr("height", function(d) {
    return Math.abs(y(d.value) - y(0));
  });
  g.append("g")
  .attr("class", "x axis")
  .attr("transform", "translate(0," + y(0) + ")")
  .call(xAxis);

	.axis {
	  font: 10px sans-serif;
	}

	.axis path,
	.axis line {
	  fill: none;
	  stroke: #000;
	  shape-rendering: crispEdges;
	}

	.blue:hover {
	  fill: steelblue;
	}

	.red:hover {
	  fill: brown;
	}

	.red {
	  fill: red;
	}

	.blue {
	  fill: blue;
	}

<script src="https://d3js.org/d3.v4.min.js"></script>

关于javascript - 将 x 轴与零刻度 d3 条形图对齐，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/46674301/