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--description--

The last challenge created a bar chart, but there are a couple of formatting changes that could improve it:

  1. Add space between each bar to visually separate them, which is done by adding a margin to the CSS for the bar class

  2. Increase the height of the bars to better show the difference in values, which is done by multiplying the value by a number to scale the height

--instructions--

First, add a margin of 2px to the bar class in the style tag. Next, change the callback function in the style() method so it returns a value 10 times the original data value (plus the px).

Note: Multiplying each data point by the same constant only alters the scale. It's like zooming in, and it doesn't change the meaning of the underlying data.

--hints--

The first div should have a height of 120 pixels and a margin of 2 pixels.

assert(
  $('div').eq(0).css('height') == '120px' &&
    $('div').eq(0).css('margin-right') == '2px'
);

The second div should have a height of 310 pixels and a margin of 2 pixels.

assert(
  $('div').eq(1).css('height') == '310px' &&
    $('div').eq(1).css('margin-right') == '2px'
);

The third div should have a height of 220 pixels and a margin of 2 pixels.

assert(
  $('div').eq(2).css('height') == '220px' &&
    $('div').eq(2).css('margin-right') == '2px'
);

The fourth div should have a height of 170 pixels and a margin of 2 pixels.

assert(
  $('div').eq(3).css('height') == '170px' &&
    $('div').eq(3).css('margin-right') == '2px'
);

The fifth div should have a height of 250 pixels and a margin of 2 pixels.

assert(
  $('div').eq(4).css('height') == '250px' &&
    $('div').eq(4).css('margin-right') == '2px'
);

The sixth div should have a height of 180 pixels and a margin of 2 pixels.

assert(
  $('div').eq(5).css('height') == '180px' &&
    $('div').eq(5).css('margin-right') == '2px'
);

The seventh div should have a height of 290 pixels and a margin of 2 pixels.

assert(
  $('div').eq(6).css('height') == '290px' &&
    $('div').eq(6).css('margin-right') == '2px'
);

The eighth div should have a height of 140 pixels and a margin of 2 pixels.

assert(
  $('div').eq(7).css('height') == '140px' &&
    $('div').eq(7).css('margin-right') == '2px'
);

The ninth div should have a height of 90 pixels and a margin of 2 pixels.

assert(
  $('div').eq(8).css('height') == '90px' &&
    $('div').eq(8).css('margin-right') == '2px'
);

--seed--

--seed-contents--​

<style>
  .bar {
    width: 25px;
    height: 100px;
    /* Add your code below this line */

    
    /* Add your code above this line */
    display: inline-block;
    background-color: blue;
  }
</style>
<body>
  <script>
    const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];

    d3.select("body").selectAll("div")
      .data(dataset)
      .enter()
      .append("div")
      .attr("class", "bar")
      .style("height", (d) => (d + "px")) // Change this line
  </script>
</body>

--solutions--

<style>
  .bar {
    width: 25px;
    height: 100px;
    margin: 2px;
    display: inline-block;
    background-color: blue;
  }
</style>
<body>
  <script>
    const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];

    d3.select("body").selectAll("div")
      .data(dataset)
      .enter()
      .append("div")
      .attr("class", "bar")
      .style("height", (d) => (d * 10 + "px"))
  </script>
</body>