Benchmark: Array filter vs Lodash intersection

Script Preparation code:

var arr1 = [];
for (let i = 0; i < 1000; i++) {
  arr1.push(i);
}
arr1 = _.shuffle(arr1);

var arr2 = [];
for (let i = 500; i < 1500; i++) {
  arr2.push(i);
}
arr2 = _.shuffle(arr2);

Tests:

Native
arr1.filter(item => arr2.indexOf(item) > -1);
Lodash
_.intersection(arr1, arr2);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Native
Lodash

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one month ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:130.0) Gecko/20100101 Firefox/130.0

Browser/OS: Firefox 130 on Linux

View result in a separate tab

Test name	Executions per second
Native	1706.1 Ops/sec
Lodash	4262.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested.

**Benchmark Definition**

The benchmark is comparing two approaches to find common elements between two arrays:

1. **Native**: Using the `filter` method with an arrow function that checks if an element is present in the second array using `indexOf`.
2. **Lodash**: Using the `intersection` function from the Lodash library, which takes two arrays as input and returns a new array containing only the elements that are common to both.

**Options Compared**

The benchmark is comparing these two approaches:

* **Native**: Using the built-in `filter` method with an arrow function.
* **Lodash**: Using the `intersection` function from Lodash library.

**Pros and Cons of Each Approach**

1. **Native**:
	* Pros: No additional dependency (Lodash), potentially faster execution since it's a native JavaScript method.
	* Cons: May be slower due to the overhead of calling an external library, especially for smaller arrays.
2. **Lodash**:
	* Pros: Potentially faster execution since Lodash is optimized for performance, comes with a larger community and more extensive documentation.
	* Cons: Requires including the Lodash library, which may increase bundle size.

**Other Considerations**

The benchmark also considers the impact of array shuffling on performance. The script preparation code shuffles both arrays using `_.shuffle(arr1)` and `arr2 = _.shuffle(arr2)`, which ensures that the arrays are randomly distributed before running the benchmarks. This helps to mitigate any biases in the results due to array ordering or distribution.

**Library: Lodash**

Lodash is a popular JavaScript utility library that provides a wide range of functions for tasks such as array manipulation, string processing, and more. The `intersection` function is part of Lodash's "More Utilities" module and takes two arrays as input and returns a new array containing only the elements that are common to both.

**Special JS Feature/Syntax**

There isn't any specific JavaScript feature or syntax being tested in this benchmark. However, it's worth noting that arrow functions (e.g., `item => arr2.indexOf(item) > -1`) are used in both benchmarks, which is a relatively modern JavaScript feature introduced in ECMAScript 2015.

**Alternatives**

If you're looking for alternative approaches to find common elements between two arrays, you could consider:

* Using the `set` data structure and set intersection operations.
* Utilizing libraries like FastUtils or Array-Intersect.
* Implementing a custom solution using bitwise operations and array iteration.

Related benchmarks:

Array filter vs Lodash intersection (version: 0)

Comparing performance of: Native vs Lodash

Created: 4 years ago by: Guest

Jump to the latest result

Native

Lodash

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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