Benchmark: Array diff2 - MeasureThat.net

HTML Preparation code:

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

Script Preparation code:

function dec2hex (dec) {
  return dec < 10
    ? '0' + String(dec)
    : dec.toString(16)
}

function generateId (len) {
  var arr = new Uint8Array((len || 40) / 2)
  window.crypto.getRandomValues(arr)
  return Array.from(arr, dec2hex).join('')
}

var a = []
var b = []
for( let i = 0; i < 1000; i++)
{
  a[i] = generateId(16)
  b[i] = generateId(16)
}

var bs = new Set(b)

Tests:

lodash
const res = _.xor(a, b).lenght === 0;
set diff
const res = a.length === b.length && a.every((x) => bs.has(x))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash
set diff

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 24 days ago):

LLMs can make mistakes. Check important info.

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

**Benchmark Definition**

The benchmark is testing two different approaches to find the difference between two arrays, `a` and `b`.

1. **Lodash**: The benchmark uses Lodash, a popular JavaScript library for functional programming tasks. In this case, it tests the `xor` function from Lodash, which returns an array containing elements that are present in either of the input arrays but not both.
2. **Set Difference**: The other approach uses a simple set difference calculation to find the elements that are present in one array but not the other.

**Options Compared**

We have two options being compared:

1. **Lodash**: Uses Lodash's `xor` function, which is a built-in implementation for finding differences between arrays.
2. **Set Difference**: Uses a simple set difference calculation using a `Set` data structure to find elements that are present in one array but not the other.

**Pros and Cons**

1. **Lodash**:
	* Pros: Fast and efficient, well-tested, and widely adopted.
	* Cons: Adds an external dependency (Lodash), which may incur additional overhead.
2. **Set Difference**:
	* Pros: Lightweight, no external dependencies required, and easy to implement.
	* Cons: May be slower than Lodash's optimized implementation, and requires manual handling of edge cases.

**Library: Set**

The `Set` data structure is a built-in JavaScript object that allows you to store unique values. In this benchmark, it's used to find elements that are present in one array but not the other by checking if each element is already present in the set.

**Special JS Feature/Syntax: None**

There are no special JavaScript features or syntax being used in this benchmark.

**Other Alternatives**

If you're looking for alternative implementations of array difference algorithms, here are a few options:

1. **Splice**: You can use `splice` to remove elements from one array and add them to another.
2. **Slice**: You can use `slice` to create a new array with only the desired elements.
3. **Filter**: You can use `filter` to create a new array with elements that meet a certain condition.

However, these alternatives may not be as efficient or well-tested as Lodash's implementation or the set difference approach used in this benchmark.

In summary, the benchmark is testing two different approaches to find the difference between two arrays: using Lodash's `xor` function and a simple set difference calculation. The pros and cons of each approach highlight the trade-offs between using an external library (Lodash) versus a lightweight, manual implementation (set difference).

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Windows

View result in a separate tab

Test name	Executions per second
lodash	1903.1 Ops/sec
set diff	2217234.8 Ops/sec

Related benchmarks:

Array diff2 (version: 0)

Comparing performance of: lodash vs set diff

Created: one year ago by: Guest

Jump to the latest result

lodash

set diff

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 24 days ago):