Javascript Range Function

29 October 2021

Updated: 03 September 2023

Something i often find myself needing is a way to create a range in javascript, similar to what python has

Here’s a basic implementation of something that works like that:

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const range = (start, end, count, includeEnd = false) => {
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  const space = (end - start) / (count - includeEnd)
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  return new Array(count).fill(0).map((_, i) => start + i * space)
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}

The above will output something like:

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const withoutEnd = range(20, 21, 5)
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// withoutEnd === [ 20, 20.2, 20.4, 20.6, 20.8 ]
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const withEnd = range(20, 21, 5, true)
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// withEnd === [ 20, 20.25, 20.5, 20.75, 21 ]