Benchmark: uniqBy performance

HTML Preparation code:

<script>https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.core.js</script>

Script Preparation code:

var data = [{a: 1}, {a: 2}, {a: 3}, {a: 4}, {a: 5}, {a: 6}, {a: 7}, {a: 8}, {a: 1}];

Tests:

lodash
_.uniqBy(data, 'a');
javascript
const sortBy = (key) => { return (a, b) => (a[key] > b[key]) ? 1 : (b[key] > a[key] ? -1 : 0); }; const uniqBy = (arr, a) => { arr.sort(sortBy(a)); const arr1 = []; arr1.push(arr[0]); for (let index = 1; index < arr.length; index++) { if (arr[index-1] && arr[index -1].a !== arr[index].a) { arr1.push(arr[index]); } } return arr1; } uniqBy(data, 'a')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash
javascript

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:120.0) Gecko/20100101 Firefox/120.0

Browser/OS: Firefox 120 on Ubuntu

View result in a separate tab

Test name	Executions per second
lodash	1777446.1 Ops/sec
javascript	2259416.2 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

The provided benchmark measures the performance of two approaches to create an array with unique elements, sorted by a specific attribute.

**Script Preparation Code and Options Compared**

The script preparation code for this benchmark is a JavaScript array `data` that contains 9 elements, including duplicates. The array has an attribute `a` that can be used as a key for sorting or filtering the elements.

Two options are compared:

1. **Lodash (`_.uniqBy(data, 'a')`)**: This approach uses the `uniqBy` function from the Lodash library, which removes duplicate elements based on a specified attribute. The function sorts the array first and then iterates through it to filter out duplicates.
2. **Custom JavaScript implementation (`const uniqBy = (arr, a) => { ... }; uniqBy(data, 'a')`)**: This approach implements a custom `uniqBy` function that uses the `sort()` method to sort the array by the specified attribute and then iterates through it to filter out duplicates.

**Pros and Cons of Each Approach**

1. **Lodash (`_.uniqBy(data, 'a')`)**:
	* Pros: Fast and efficient, as Lodash is a well-optimized library.
	* Cons: Requires an additional external library (Lodash) to be included in the project, which can increase bundle size.
2. **Custom JavaScript implementation (`const uniqBy = (arr, a) => { ... }; uniqBy(data, 'a')`)**:
	* Pros: No external dependencies required, and can be optimized for specific use cases.
	* Cons: Requires more manual effort to implement the logic correctly and maintainably.

**Library Used**

The Lodash library is used in this benchmark. Lodash is a popular JavaScript utility library that provides a wide range of functions for tasks like array manipulation, string manipulation, and data processing.

**Special JS Feature or Syntax**

None are explicitly mentioned in the provided code snippet. However, it's worth noting that some modern JavaScript features like `const` and arrow functions (`=>`) are used in the custom implementation.

**Other Alternatives**

If you prefer not to use Lodash or implement a custom solution, other alternatives for creating an array with unique elements include:

1. **Set**: You can convert the array to a Set data structure, which automatically removes duplicates. Then, iterate through the Set and create a new array with only the unique elements.
2. **Array.prototype.reduce()**: Similar to using Set, you can use `reduce()` method to iterate through the array and collect unique elements.

Example code:
```javascript
const uniqBySet = (arr, a) => [...new Set(arr.map(item => item[a]))].map(item => arr.find(i => i[a] === item));
```
Keep in mind that these alternatives might have slightly different performance characteristics compared to Lodash or the custom implementation.

Related benchmarks:

uniqBy performance (version: 0)

lodash vs javascript

Comparing performance of: lodash vs javascript

Created: 6 years ago by: Registered User

Jump to the latest result

lodash

javascript

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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