javascript - D3.js 图表随机数据或天气 API

Question

*[感谢 Gerardo Furtado 找到解决方案]

我是编码新手，目前正在从事太阳能/风能预测元素。在我的设计中，我需要一个图表来显示 future 一周的千瓦发电量预测。我一直在尝试根据找到的教程 here 将数据从 Dark Sky API 连接到下图。 。我现在尝试用随机生成的数字作为虚拟数据替换频率数据值，但不知道如何执行此操作。关于如何解决这个问题有什么建议吗？谢谢。

index.html:

    <script>

    var margin = {top: 40, right: 20, bottom: 30, left: 40},
        width = 900 - margin.left - margin.right,
        height = 500 - margin.top - margin.bottom;

    var formatPercent = d3.format("0");

    var x = d3.scale.ordinal()
        .rangeRoundBands([0, width], .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")
        .tickFormat(formatPercent);

    var tip = d3.tip()
      .attr('class', 'd3-tip')
      .offset([-10, 0])
      .html(function(d) {
        return "<strong>Predicted KW Total:</strong> <span style='color:#FFD15B'>" + d.frequency + "</span>";
      })


    var svg = d3.select("#chart").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 + ")");

    svg.call(tip);

    d3.tsv("data.tsv", type, function(error, data) {
      x.domain(data.map(function(d) { return d.letter; }));
      y.domain([0, d3.max(data, function(d) { return d.frequency; })]);

      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("Kilowatts (KW)");

      svg.selectAll(".bar")
          .data(data)
        .enter().append("rect")
          .attr("class", "bar")
          .attr("x", function(d) { return x(d.letter); })
          .attr("width", x.rangeBand())
          .attr("y", function(d) { return y(d.frequency); })
          .attr("height", function(d) { return height - y(d.frequency); })
          .on('mouseover', tip.show)
          .on('mouseout', tip.hide)

    });

    d3.select("#chart").attr("align","center");

    function type(d) {
      d.frequency = +d.frequency;
      return d;
    }
    </script>

CSS:

<style>

#chart {
 background-color: #FFFFFF;
 float:left;
 width: 80%;
 height: 550px;
 padding-top: 25px;
}

.light {
 font-weight: bold;
 color: #717070;
}

.tagline {
 text-align: center;
 color: #FFFFFF;
 margin-top: 4px;
 font-weight: lighter;
 text-transform: uppercase;
 letter-spacing: 1px;
}

bod {
 font: 10px sans-serif;
}

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

.bar:hover {
 fill: #FFD15B;
}

.x.axis path {
 display: none;
}

.d3-tip {
 line-height: 1;
 font-weight: bold;
 padding: 12px;
 background: rgba(0, 0, 0, 0.8);
 color: #fff;
 border-radius: 2px;
}

.d3-tip:after {
box-sizing: border-box;
display: inline;
font-size: 10px;
width: 100%;
line-height: 1;
color: rgba(0, 0, 0, 0.8);
content: "\25BC";
position: absolute;
text-align: center;
}

.d3-tip.n:after {
 margin: -1px 0 0 0;
 top: 100%;
 left: 0;
}

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

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

.bar {
    fill: #D47039;
}

.x.axis path {
 display: none;
}

label {
 position: absolute;
 top: 10px;
 right: 10px;
}
</style>

数据.tsv:

letter  frequency
Sun 10
Mon 20
Tues 5
Wed 10
Thurs 30
Fri 15
Sat 8

Answer 1

由于您只需要用随机值替换该 TSV，因此创建一个包含日期的数组:

var days = ["Sun", "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat"];

并根据days创建您自己的data数组:

var data = [];

days.forEach(function(d) {
    data.push({
        letter: d,
        frequency: ~~(Math.random() * 30)
    })
})

这是一个工作演示:

var days = ["Sun", "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat"];

var data = [];

days.forEach(function(d) {
  data.push({
    letter: d,
    frequency: ~~(Math.random() * 30)
  })
})

var margin = {
    top: 40,
    right: 20,
    bottom: 30,
    left: 40
  },
  width = 900 - margin.left - margin.right,
  height = 500 - margin.top - margin.bottom;

var formatPercent = d3.format("0");

var x = d3.scale.ordinal()
  .rangeRoundBands([0, width], .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")
  .tickFormat(formatPercent);

var tip = d3.tip()
  .attr('class', 'd3-tip')
  .offset([-10, 0])
  .html(function(d) {
    return "<strong>Predicted KW Total:</strong> <span style='color:#FFD15B'>" + d.frequency + "</span>";
  })


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 + ")");

svg.call(tip);


x.domain(data.map(function(d) {
  return d.letter;
}));
y.domain([0, d3.max(data, function(d) {
  return d.frequency;
})]);

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("Kilowatts (KW)");

svg.selectAll(".bar")
  .data(data)
  .enter().append("rect")
  .attr("class", "bar")
  .attr("x", function(d) {
    return x(d.letter);
  })
  .attr("width", x.rangeBand())
  .attr("y", function(d) {
    return y(d.frequency);
  })
  .attr("height", function(d) {
    return height - y(d.frequency);
  })
  .on('mouseover', tip.show)
  .on('mouseout', tip.hide)

.light {
  font-weight: bold;
  color: #717070;
}

.tagline {
  text-align: center;
  color: #FFFFFF;
  margin-top: 4px;
  font-weight: lighter;
  text-transform: uppercase;
  letter-spacing: 1px;
}

bod {
  font: 10px sans-serif;
}

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

.bar:hover {
  fill: #FFD15B;
}

.x.axis path {
  display: none;
}

.d3-tip {
  line-height: 1;
  font-weight: bold;
  padding: 12px;
  background: rgba(0, 0, 0, 0.8);
  color: #fff;
  border-radius: 2px;
}

.d3-tip:after {
  box-sizing: border-box;
  display: inline;
  font-size: 10px;
  width: 100%;
  line-height: 1;
  color: rgba(0, 0, 0, 0.8);
  content: "\25BC";
  position: absolute;
  text-align: center;
}

.d3-tip.n:after {
  margin: -1px 0 0 0;
  top: 100%;
  left: 0;
}

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

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

.bar {
  fill: #D47039;
}

.x.axis path {
  display: none;
}

label {
  position: absolute;
  top: 10px;
  right: 10px;
}

<script src="https://d3js.org/d3.v3.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3-tip/0.7.1/d3-tip.min.js"></script>