Benchmark: Unique Lodash vs Set

HTML Preparation code:

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

Script Preparation code:

var a = [],i;
for (i = 0; i < 1000; i++) 
    a.push(Math.floor(Math.random() * 1000) + 1);

var unique = (function(){
  let keys = Object.keys;
  return function(arr){
    let ob = {};
    let len = arr;
    let retArr=[];
    for(let i=0;i<len;i++){
      if(ob[arr[i]] === undefined){
     	ob[arr[i]]=1;
        retArr.push(arr[i]);
      }
    }
    return retArr;
  }
}());

Tests:

Lodash
_.uniq(a)
Set Spread based
[... new Set(a)]
Set ArrayFrom based
Array.from(new Set(a))
Object Based Unique
unique(a)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Lodash
Set Spread based
Set ArrayFrom based
Object Based Unique

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.5845.2319 YaBrowser/23.9.0.2319 Yowser/2.5 Safari/537.36

Browser/OS: Yandex Browser 23 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Lodash	42371.3 Ops/sec
Set Spread based	61689.1 Ops/sec
Set ArrayFrom based	61623.5 Ops/sec
Object Based Unique	75802.6 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll explain the benchmark and its options.

**Benchmark Overview**

The benchmark measures the performance of three different approaches to remove duplicates from an array: Lodash's `uniq` function, `Set` spread operator (`[... new Set(a)]`), and `Array.from(new Set(a))`. The benchmark uses a fixed input size of 1000 random integers.

**Options Compared**

1. **Lodash's `uniq` function**: This approach uses the `Object.keys` function to get an array of keys from the input array, which is then used to create a new object with unique values as keys. The resulting values are returned as an array.
2. **Set spread operator (`[... new Set(a)]`)**: This approach uses the spread operator to create a new `Set` object from the input array, which automatically removes duplicates. The `Set` object is then converted back to an array using the spread operator again.
3. **Array.from(new Set(a))**: This approach creates a new `Set` object from the input array and then uses the `Array.from()` method to convert it back to an array.

**Pros and Cons of Each Approach**

1. **Lodash's `uniq` function**:
	* Pros: Can be used with other Lodash functions, has built-in support for handling multiple values.
	* Cons: May have performance overhead due to the use of `Object.keys`.
2. **Set spread operator (`[... new Set(a)]`)**:
	* Pros: Fast and efficient, easy to read and write.
	* Cons: Requires a modern browser that supports the spread operator.
3. **Array.from(new Set(a))**:
	* Pros: Also fast and efficient, can be used with other array methods.
	* Cons: May have performance overhead due to the creation of an intermediate `Set` object.

**Library Used**

The benchmark uses Lodash version 4.17.5, which is a popular utility library for JavaScript that provides various functions for working with arrays, objects, and more.

**Special JS Features/Syntax**

None are mentioned in this specific benchmark.

**Other Considerations**

When choosing an approach, consider the following factors:

* Performance: The `Set` spread operator and `Array.from(new Set(a))` approaches are likely to be the fastest.
* Browser support: If you need to support older browsers, Lodash's `uniq` function may be a better choice.
* Code readability: The `Set` spread operator approach is often considered more readable than Lodash's `uniq` function.

**Alternatives**

Other alternatives for removing duplicates from an array include:

1. Using a `Map` object with the input array as values, which automatically removes duplicates.
2. Using a custom implementation that uses a hash table or other data structure to keep track of unique elements.
3. Using a library like `fast-json-stamp` which provides a fast and efficient way to remove duplicates from an array.

Note: The performance of these alternatives may vary depending on the specific use case and requirements.

Related benchmarks:

Unique Lodash vs Set (version: 0)

Comparing performance of: Lodash vs Set Spread based vs Set ArrayFrom based vs Object Based Unique

Created: 4 years ago by: Registered User

Jump to the latest result

Lodash

Set Spread based

Set ArrayFrom based

Object Based Unique

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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