Benchmark: Filter unique, lodash vs Set vs filter()

HTML Preparation code:

<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/lodash@4.17.10/lodash.min.js"></script>

Script Preparation code:

function filterUniq(arr){
	return arr.filter((i,p)=>{
      return arr.indexOf(i) == p
    }); 
}
function setUniq(arr){
	return [...new Set(arr)] 
}
var a = [1, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5]

Tests:

Filter
var b = filterUniq(a)
Set
var b = setUniq(a)
lodash
var b = _.uniq(a)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Filter
Set
lodash

Fastest: N/A

Slowest: N/A

Latest run results:

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

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Let's dive into the world of JavaScript microbenchmarks.

**Benchmark Overview**

The benchmark in question is designed to compare three approaches for removing duplicates from an array: `filterUniq`, `setUniq`, and `_.uniq` (a function from the Lodash library). The test case uses a large array with repeated values, and each approach is executed repeatedly to measure their performance.

**Approaches Compared**

1. **`filterUniq`**: This implementation uses the `indexOf` method to check if an element exists in the original array. If it does, it returns `false`, effectively filtering out duplicates.
2. **`setUniq`**: This approach uses the `Set` data structure to store unique elements. It converts the input array to a set and then back to an array using the spread operator (`...`). This method relies on JavaScript's built-in set implementation, which has an average time complexity of O(1) for insertion and lookup operations.
3. **`_.uniq` (Lodash)**: This function uses a similar approach to `filterUniq`, but with a more concise syntax. It iterates over the input array using `forEach`, checking each element against its index in the original array.

**Pros and Cons of Each Approach**

1. **`filterUniq`**:
	* Pros: Simple, easy to understand.
	* Cons: Has a higher time complexity due to repeated `indexOf` calls (O(n^2) for large arrays).
2. **`setUniq`**:
	* Pros: Efficient use of JavaScript's built-in sets, making it suitable for large datasets.
	* Cons: Requires modern browsers or environments that support `Set`, and may not work as expected in older versions.
3. **`_.uniq` (Lodash)**:
	* Pros: Compact syntax, easy to read.
	* Cons: Has a slightly higher time complexity than `setUniq` due to the use of `forEach` (O(n)).

**Library Overview**

The Lodash library provides a collection of functional programming helpers, including `_.uniq`. Lodash is designed to be a utility belt for JavaScript developers, offering a range of functions for tasks like array manipulation, string manipulation, and more. In this benchmark, the `_.uniq` function serves as an alternative implementation for removing duplicates from an array.

**Specialized JavaScript Feature or Syntax**

The benchmark does not use any specialized JavaScript features or syntax beyond what's already discussed (e.g., `Set`, `forEach`). However, it's worth noting that modern JavaScript engines have introduced additional features like `Promise` and `async/await` which can affect performance in certain scenarios. These features are not explicitly used in the benchmark.

**Other Alternatives**

For removing duplicates from an array, other approaches could include:

* Using a more efficient data structure like a `Map` or a `TreeSet`.
* Implementing a custom algorithm using bitwise operations or other low-level techniques.
* Utilizing specialized libraries or frameworks that provide optimized duplicate removal functionality (e.g., some sorting algorithms).

These alternatives may have varying trade-offs in terms of performance, readability, and maintainability. The choice of approach depends on the specific use case, performance requirements, and personal preference.

Related benchmarks:

Filter unique, lodash vs Set vs filter() (version: 0)

Comparing performance of: Filter vs Set vs lodash

Created: 7 years ago by: Guest

Jump to the latest result

Filter

Set

lodash

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):