折线图中的路径太小

Question

我目前正在使用 d3.js 创建折线图，但遇到了路径宽度和高度正确的问题。

const margin = {
  top: 50,
  right: 50,
  bottom: 50,
  left: 50
}
const width = 700
const height = 500
const dateConv = d3.timeParse("%Y-%m-%d")

const svg = d3.select("#temparatureGraph").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 + ")")

d3.xml("https://raw.githubusercontent.com/ForceSergeant/D3LineGraph/6aa5b375dbc0bd2ca86f6fcef73369caae64232e/data.xml")
  .then((xml) => {

    let values = []
    let dates = []
    let times = []

    //Processign the data
    const document = d3.select(xml.documentElement)
    const temperature = document.selectAll('temperature')
    temperature.selectAll("average").each(function() {
      values.push(+this.textContent)
    })
    const date = document.selectAll('utc')
    date.selectAll("date").each(function() {
      dates.push(dateConv(this.textContent))
    })
    const time = document.selectAll('utc')
    time.selectAll("time").each(function() {
      times.push(this.textContent)
    })

    console.log(dates)
    console.log(times)

    dates = dates.map((value, index) => {
      value.setHours(times[index].split(":")[0])
      return value
    })

    const data = []
    for (var i = 0; i < dates.length; i++) {
      data.push({
        date: dates[i],
        value: values[i]
      })
    }

    console.log(data)


    const xScale = d3.scaleTime().range([0, width])
    const yScale = d3.scaleLinear().range([height, 0])

    xScale.domain(d3.extent(data, d => d.date))
    yScale.domain([d3.min(data, d => d.value), d3.max(data, d => d.value)])

    const xaxis = d3.axisBottom()
      .ticks(d3.timeMonth.every(1))
      .tickFormat(d3.timeFormat('%b %y'))
      .scale(xScale);
    const yaxis = d3.axisLeft().scale(yScale);

    //x-Achse
    svg.append("g")
      .attr("class", "axis")
      .attr("transform", "translate(0," + height + ")")
      .call(xaxis);

    //y-Achse
    svg.append("g")
      .attr("class", "axis")
      .call(yaxis)
      .append("text")
      .attr("transform", "rotate(-90)")
      .attr("dy", ".75em")
      .attr("y", 6)
      .style("text-anchor", "end")
      .text("Grad Celsius");

    const line = d3.line()
      .x(function(d) {
        return xScale(d.date);
      })
      .y(function(d) {
        return yScale(d.value);
      });

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

.axis line {
    stroke: red;
}

/* axis contour */
.axis path {
    stroke: green;
}

/* axis text */
.axis text {
    fill: blue;
}

.dataPath {
    fill: none;
    stroke: gold;
    stroke-miterlimit: 1;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/5.7.0/d3.min.js"></script>
<div id="temparatureGraph"></div>

• Values 是每天和每小时的温度数组
• 日期是一个数组，对应的日期
• Times 是对应时间的数组 数据是一个obj数组，格式如下：[{date: , value: }]

一切正常，但路径太小，不适合您在图像中看到的 x 轴。

她是XML-file。

感谢您的每一个帮助。

Answer 1

您的示例中缺少一些数据，特别是在 2018 年 1 月 31 日，value 是 NaN。

在 d3 中，您需要设置折线图可以跳过哪些值，否则它会尝试绘制它们、中断，并且（无益地）在没有警告的情况下退出。您可以使用d3.line().defined() 来执行此操作，我在下面的（放大的）示例中执行了此操作。请注意线路如何停止现有并稍后重新启动。

const margin = {
  top: 50,
  right: 50,
  bottom: 50,
  left: 50
}
const width = 700
const height = 500
const dateConv = d3.timeParse("%Y-%m-%d")

const svg = d3.select("#temparatureGraph").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 + ")")

d3.xml("https://raw.githubusercontent.com/ForceSergeant/D3LineGraph/6aa5b375dbc0bd2ca86f6fcef73369caae64232e/data.xml")
  .then((xml) => {

    let values = []
    let dates = []
    let times = []

    //Processign the data
    const document = d3.select(xml.documentElement)
    const temperature = document.selectAll('temperature')
    temperature.selectAll("average").each(function() {
      values.push(+this.textContent)
    })
    const date = document.selectAll('utc')
    date.selectAll("date").each(function() {
      dates.push(dateConv(this.textContent))
    })
    const time = document.selectAll('utc')
    time.selectAll("time").each(function() {
      times.push(this.textContent)
    })

    dates.forEach((value, index) => {
      value.setHours(times[index].split(":")[0])
    })

    const data = []
    // I just added this for simplicity,
    // it's unrelated to the solution
    for (var i = 700; i < 750; i++) {
      data.push({
        date: dates[i],
        value: values[i]
      })
    }

    const xScale = d3.scaleTime().range([0, width])
    const yScale = d3.scaleLinear().range([height, 0])

    xScale.domain(d3.extent(data, d => d.date))
    yScale.domain([d3.min(data, d => d.value), d3.max(data, d => d.value)]);

    const xaxis = d3.axisBottom()
      .ticks(d3.timeMonth.every(1))
      .tickFormat(d3.timeFormat('%b %y'))
      .scale(xScale);
    const yaxis = d3.axisLeft().scale(yScale);

    //x-Achse
    svg.append("g")
      .attr("class", "axis")
      .attr("transform", "translate(0," + height + ")")
      .call(xaxis);

    //y-Achse
    svg.append("g")
      .attr("class", "axis")
      .call(yaxis)
      .append("text")
      .attr("transform", "rotate(-90)")
      .attr("dy", ".75em")
      .attr("y", 6)
      .style("text-anchor", "end")
      .text("Grad Celsius");

    const line = d3.line()
      .defined(function(d) { return !isNaN(d.value); })
      .x(function(d) {
        return xScale(d.date);
      })
      .y(function(d) {
        return yScale(d.value);
      });

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

.axis line {
    stroke: red;
}

/* axis contour */
.axis path {
    stroke: green;
}

/* axis text */
.axis text {
    fill: blue;
}

.dataPath {
    fill: none;
    stroke: gold;
    stroke-miterlimit: 1;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/5.7.0/d3.min.js"></script>
<div id="temparatureGraph"></div>