Benchmark: uniqBy vs findIndex

HTML Preparation code:

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

Script Preparation code:

var MyArr = Array.from({length: 40}, () => Math.floor(Math.random() * 40));

var myCopy = null;

Tests:

uniqBy
myCopy = _.uniqBy(MyArr);
findIndex
myCopy = myCopy.filter( (dependentNode, index, dependentNodesArr) => dependentNodesArr.findIndex( (currentNode) => currentNode.id === dependentNode.id ) === index )

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
uniqBy
findIndex

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser/OS: Chrome 120 on Windows

View result in a separate tab

Test name	Executions per second
uniqBy	663582.2 Ops/sec
findIndex	3316585.8 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark JSON and explain what's being tested, compared, and their pros and cons.

**Benchmark Definition JSON**

The benchmark is testing two approaches to removing duplicates from an array: `uniqBy` using Lodash's `uniqBy` function, and a custom implementation using `findIndex`.

**Script Preparation Code**
```javascript
var MyArr = Array.from({length: 40}, () => Math.floor(Math.random() * 40));
var myCopy = null;
```
This code creates an array `MyArr` with 40 random elements. The `myCopy` variable is initialized but not used anywhere in the benchmark, which seems like a mistake.

**Html Preparation Code**
```javascript
<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>
```
This code includes the Lodash library, which provides the `uniqBy` function being tested.

**Individual Test Cases**

1. **uniqBy**

The benchmark definition is:
```javascript
myCopy = _.uniqBy(MyArr);
```
This uses Lodash's `uniqBy` function to remove duplicates from `MyArr`. The `_.uniqBy` function takes an array and a function that defines the unique identifier for each element.

Lodash's `uniqBy` is a useful utility function that allows you to easily remove duplicates based on any property of an object. It returns a new array with unique elements, preserving the original order.

Pros:

* Easy to use: simply pass in the array and the unique identifier function.
* Fast performance: optimized for large arrays.

Cons:

* Dependencies Lodash: requires including the library in your HTML file.
* May not be suitable for all data formats (e.g., arrays of objects with nested properties).

2. **findIndex**

The benchmark definition is:
```javascript
myCopy = myCopy.filter(
  (dependentNode, index, dependentNodesArr) => 
    dependentNodesArr.findIndex((currentNode) => currentNode.id === dependentNode.id) === index
);
```
This custom implementation uses `filter` to remove duplicates from `MyArr`. It checks each element against every other element in the array using `findIndex`, which returns the index of the first element that matches a given condition. The comparison is done using `===` for strict equality.

Pros:

* No dependencies: no additional libraries are required.
* Simple implementation: only uses built-in functions.

Cons:

* Performance: this approach has higher overhead due to the nested loops and function calls.
* Error-prone: if the unique identifier function is not correctly implemented, it may produce incorrect results or throw errors.

**Other Considerations**

When choosing between `uniqBy` and a custom implementation like `findIndex`, consider the following factors:

* Performance: Lodash's `uniqBy` is generally faster than a custom implementation due to its optimized algorithm.
* Maintainability: if you need to modify the unique identifier function, Lodash's `uniqBy` makes it easy to do so without changing the underlying code.
* Dependencies: if you want to avoid including additional libraries in your project, a custom implementation may be preferred.

**Alternatives**

Other alternatives for removing duplicates from an array include:

* Using a data structure like a Set or Map, which automatically removes duplicates and has fast lookup times.
* Using a sorting algorithm followed by a `reduce` function to remove duplicates.
* Implementing a hash-based approach using a library like `fast-hash`.

However, these alternatives may have different trade-offs in terms of performance, maintainability, and dependencies.

Related benchmarks:

uniqBy vs findIndex (version: 0)

Comparing performance of: uniqBy vs findIndex

Created: 2 years ago by: Guest

Jump to the latest result

uniqBy

findIndex

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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