2018-10-12 15:37:13 -04:00
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---
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title: Use Dynamic Scales
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---
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2019-07-24 00:59:27 -07:00
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# Use Dynamic Scales
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---
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## Hints
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2018-10-12 15:37:13 -04:00
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2019-05-16 21:34:08 +05:30
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### Hint 1
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2018-10-12 15:37:13 -04:00
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2019-05-16 21:34:08 +05:30
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Use the `.domain()` and `.range()` functions.
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2018-10-12 15:37:13 -04:00
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2019-05-16 21:34:08 +05:30
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### Hint 2
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Use a callback function on the `.domain()` function.
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### Hint 3
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Both the `.domain()` and `.range()` functions accept an array or two elements.
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### Hint 4
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Subtract padding from height to get SVG height including padding.
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2019-07-24 00:59:27 -07:00
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---
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## Solutions
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<details><summary>Solution 1 (Click to Show/Hide)</summary>
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2019-05-16 21:34:08 +05:30
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To solve the solution by including all the hints, set the `yScale` variable to:
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```js
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const yScale = d3.scaleLinear()
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.domain([0, d3.max(dataset, (d) => d[1])])
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.range([h - padding, padding]);
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```
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The full solution now looks like:
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```html
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<body>
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<script>
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const dataset = [
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[ 34, 78 ],
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[ 109, 280 ],
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[ 310, 120 ],
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[ 79, 411 ],
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[ 420, 220 ],
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[ 233, 145 ],
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[ 333, 96 ],
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[ 222, 333 ],
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[ 78, 320 ],
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[ 21, 123 ]
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];
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const w = 500;
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const h = 500;
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// Padding between the SVG canvas boundary and the plot
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const padding = 30;
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// Create an x and y scale
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const xScale = d3.scaleLinear()
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.domain([0, d3.max(dataset, (d) => d[0])])
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.range([padding, w - padding]);
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const yScale = d3.scaleLinear()
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.domain([0, d3.max(dataset, (d) => d[1])])
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.range([h - padding, padding]);
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const output = yScale(411);
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d3.select("body")
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.append("h2")
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.text(output);
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</script>
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</body>
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```
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2019-07-24 00:59:27 -07:00
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</details>
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