Benchmark: Intersection of multiple sorted arrays | Lodash _.intersection() vs Various custom optimized methods

HTML Preparation code:

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

Script Preparation code:

var arr1 = [];
var arr2 = [];
var arr3 = [];
var arr4 = [];

for (i = 0; i < 1000; i++) {
    arr1.push(getRandom());
    arr2.push(getRandom());
    arr3.push(getRandom());
    arr4.push(getRandom());

    arr1.sort();
    arr2.sort();
    arr3.sort();
    arr4.sort();
}

function getRandom() {
    const minimum = 1;
    const maximum = 1000;
    var randomnumber = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
    return randomnumber;
}

Tests:

Lodash _.intersection()
const results = new Set(_.intersection(arr1, arr2, arr3, arr4));
Custom optimized function 1 (Best)
function intersectMultipleArrays(...arrays) { if (arrays.length === 0) return new Set(); // Sort arrays by length to optimize operations arrays.sort((a, b) => a.length - b.length); // Start with the smallest array as the base intersection set let intersection = new Set(arrays[0]); // Iterate over the remaining arrays and filter the intersection for (let i = 1; i < arrays.length; i++) { intersection = new Set(arrays[i].filter(item => intersection.has(item))); // Early exit if intersection is empty if (intersection.size === 0) return new Set(); } // Return the final Set return intersection; } const results = intersectMultipleArrays(arr1, arr2, arr3, arr4);
Custom optimized function 2
const results = new Set( [arr1, arr2, arr3, arr4] .sort((a, b) => b.length - a.length) .reduce((a, b) => a.filter(aValue => b.includes(aValue))) );

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Lodash _.intersection()
Custom optimized function 1 (Best)
Custom optimized function 2

Fastest: N/A

Slowest: N/A

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/129.0.0.0 Safari/537.36

Browser/OS: Chrome 129 on Windows

View result in a separate tab

Test name	Executions per second
Lodash _.intersection()	5088.8 Ops/sec
Custom optimized function 1 (Best)	6959.0 Ops/sec
Custom optimized function 2	3813.1 Ops/sec

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

LLMs can make mistakes. Check important info.

Measuring performance differences between various JavaScript approaches to solve the same problem is crucial for optimization and development efficiency.

**Benchmark Overview**

The provided benchmark compares three different methods to find the intersection of multiple sorted arrays:

1. Lodash _.intersection(): A built-in function from the popular utility library Lodash.
2. Custom optimized function 1 (Best): A custom implementation that sorts the arrays by length, starts with the smallest array as the base intersection set, and iterates over the remaining arrays filtering the intersection.
3. Custom optimized function 2: Another custom implementation that sorts the arrays by length and then uses the `reduce()` method to filter the intersection.

**Options Compared**

The three methods are compared in terms of their execution speed.

**Pros and Cons of Each Approach**

1. **Lodash _.intersection()**:
	* Pros: Fast, well-tested, and widely adopted.
	* Cons: Not optimized for performance, may not be suitable for large datasets.
2. **Custom optimized function 1 (Best)**:
	* Pros: Optimized for performance, takes advantage of sorting by array length.
	* Cons: Requires manual implementation and debugging.
3. **Custom optimized function 2**:
	* Pros: Similar to the first custom approach but uses `reduce()` method.
	* Cons: May be less efficient than the first custom approach due to overhead of `reduce()`.

**Library Usage**

Lodash is a popular utility library that provides a wide range of functions for common tasks, including array manipulation. In this benchmark, Lodash _.intersection() is used as-is from the library.

**Special JS Features or Syntax**

None mentioned in the provided benchmark.

**Other Considerations**

* The benchmark uses a randomization technique to create multiple sets of 1000 elements each.
* The test case prepares both JavaScript code and HTML code for execution, including loading Lodash via CDN.
* The benchmark measures the number of executions per second (ExecutionsPerSecond) as a metric.

**Alternative Approaches**

Other possible approaches to find the intersection of multiple sorted arrays include:

1. Using `Array.prototype.filter()` and manual iteration.
2. Employing data structures like heaps or balanced trees for efficient intersections.
3. Leveraging library functions from other frameworks, such as jQuery UI or Lodash alternatives.

While these alternative approaches might be viable, they are not directly compared in this benchmark.

Related benchmarks:

Intersection of multiple sorted arrays | Lodash _.intersection() vs Various custom optimized methods (version: 1)

Comparing performance of: Lodash _.intersection() vs Custom optimized function 1 (Best) vs Custom optimized function 2

Created: one year ago by: Registered User

Jump to the latest result

Lodash _.intersection()

Custom optimized function 1 (Best)

Custom optimized function 2

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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