Benchmark: lodash difference vs reduce vs filter vs find

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var list_1 = []
var list_2 = []


for(var i =0;i<1000;i++){
  list_1.push(Math.random().toString(36).slice(2, 7));
}

for(var i =0;i<200;i++){
  list_2.push(Math.random().toString(36).slice(2, 7));
}

Tests:

lodash
_.difference(list_1, list_2)
reduce
var excludeMap = list_2.reduce((all, item) => ({ ...all, [item]: true }), {}); list_1.filter((item) => !excludeMap?.[item]);
set filter
var toRemove = new Set(list_2); list_1.filter(i => !toRemove.has(i))
find filter
list_1.filter(i => list_2.find(i2 => i2 === i))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash
reduce
set filter
find filter

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.0.0 Safari/537.36

Browser/OS: Chrome 102 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
lodash	16528.0 Ops/sec
reduce	131.8 Ops/sec
set filter	25704.8 Ops/sec
find filter	902.7 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in this benchmark.

**Benchmark Overview**

The benchmark measures the performance of three different approaches to exclude all elements from one array (`list_1`) based on their presence in another array (`list_2`).

**Approaches Compared**

1. **Lodash**: Uses the `_.difference` function from the Lodash library, which returns a new array containing only the elements that are present in `list_1`, but not in `list_2`.
2. **Reduce**: Uses the `reduce` method to create a map of all elements in `list_2` as keys and sets them as true, then uses this map to filter out elements from `list_1` that are not present.
3. **Set Filter**: Uses a Set data structure to store elements from `list_2`, then filters out elements from `list_1` that are not present in the Set.

**Pros and Cons of Each Approach**

1. **Lodash**:
	* Pros: Simple, concise, and well-tested function.
	* Cons: Requires an external library (Lodash), which might introduce additional overhead.
2. **Reduce**:
	* Pros: Native JavaScript function, no external dependencies.
	* Cons: Can be slower due to the creation of a map, and might require more CPU cycles for large arrays.
3. **Set Filter**:
	* Pros: Fast lookups, especially for large sets.
	* Cons: Requires creating an additional Set data structure, which can consume memory.

**Library Used**

The benchmark uses Lodash version 4.17.5, which is a popular and widely-used library for functional programming utilities in JavaScript.

**Special JS Feature/Syntax**

None of the individual test cases use any special JavaScript features or syntax that would require additional explanation.

**Other Alternatives**

Other approaches to exclude elements from an array based on their presence in another array could include:

* Using `filter()` with a callback function that checks for presence in `list_2`.
* Using a native implementation of the difference operation, such as using bitwise operations or sorting and indexing.
* Using a more modern JavaScript approach, such as using `Set` and `Map` data structures, but without using Lodash.

In general, the choice of approach depends on the specific use case, performance requirements, and personal preference.

Related benchmarks:

lodash difference vs reduce vs filter vs find (version: 0)

exclude all the elements for one array from another array

Comparing performance of: lodash vs reduce vs set filter vs find filter

Created: 2 years ago by: Guest

Jump to the latest result

lodash

reduce

set filter

find filter

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):