Benchmark: Lodash: difference vs filter

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/lodash/4.16.0/lodash.min.js"></script>

Script Preparation code:

var arrFull = ['past','present','future','a', 'b', 'c', 'd','e','f','g','h','5','6','7','8']
var arrOne = ['b']

Tests:

Difference - Full
_.difference(arrFull, arrFull)
Intersection - Full
_.filter(arrFull, (b) => arrFull.some((c) => b === c))
Difference - Partial
_.difference(arrFull, arrOne)
Intersection - Partial
_.filter(arrFull, (b) => arrOne.some((c) => b === c))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Difference - Full
Intersection - Full
Difference - Partial
Intersection - Partial

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36

Browser/OS: Chrome 129 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Difference - Full	1326006.0 Ops/sec
Intersection - Full	604907.3 Ops/sec
Difference - Partial	1903322.0 Ops/sec
Intersection - Partial	675903.2 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Overview**

The benchmark is comparing the performance of two approaches: `difference` and `filter` functions from the Lodash library, on an array of strings. The tests are divided into four cases:

1. **Difference - Full**: Comparing the full array with itself.
2. **Intersection - Full**: Finding elements that are common to both arrays.
3. **Difference - Partial**: Comparing the full array with a subset (partial) of itself, which is another array.
4. **Intersection - Partial**: Finding elements that are common to both an array and its partial version.

**Lodash Library**

The `difference` and `filter` functions are part of the Lodash library, which is a popular JavaScript utility library. Lodash provides a set of functional programming helpers, including array methods like `difference` and `filter`.

* **`.difference(arr1, arr2)`**: Returns an array containing elements that are in `arr1`, but not in `arr2`.
* `.filter(iterable, [predicate], [thisArg])`: Creates a new array with all elements from the original array for which the predicate returns `true`.

**Performance Comparison**

The benchmark tests the performance of these two approaches on different scenarios:

* **Full vs Partial**: The full array contains more elements than the partial version. This allows measuring the overhead of working with a larger dataset.
* **Self-Comparison (Difference - Full)**: The benchmark compares an array with itself, which is not typically a representative use case for performance comparison.

**Pros and Cons**

Here's a brief analysis of each approach:

1. `.difference(arrFull, arrFull)`:
	* Pros: Simple to understand, might be faster due to optimized implementation.
	* Cons: Not useful in practice, as it doesn't return any meaningful results.
2. `.filter(arrFull, (b) => arrFull.some((c) => b === c))`:
	* Pros: Can be useful in finding common elements between arrays.
	* Cons: May have higher overhead due to the use of `some()` and nested comparisons.
3. `.difference(arrFull, arrOne)`:
	* Pros: Realistic scenario for performance comparison, as it's a typical use case for filtering differences.
	* Cons: The partial array (`arrOne`) is smaller than the full array, which might affect results.
4. `.filter(arrFull, (b) => arrOne.some((c) => b === c))`:
	* Pros: Similar to scenario 3, but with a more complex filter predicate.
	* Cons: Might have higher overhead due to nested comparisons and the use of `some()`.

**Alternative Approaches**

For comparison, other approaches could be:

1. Manual implementation using loops: This would allow developers to understand exactly how performance is affected by array iteration and element comparisons.
2. Using built-in JavaScript methods like `filter()` or `map()`: These methods might have different overhead compared to Lodash's implementation.

Keep in mind that the choice of approach often depends on specific requirements, such as readability, maintainability, or optimization for performance.

**Special JS Feature**

In this benchmark, there is no special JavaScript feature being used (e.g., async/await, destructuring, etc.). If you'd like to explore features with similar concepts, I can provide information on other Lodash methods that use these features.

Related benchmarks:

Lodash: difference vs filter (version: 0)

Comparing performance of: Difference - Full vs Intersection - Full vs Difference - Partial vs Intersection - Partial

Created: 4 years ago by: Guest

Jump to the latest result

Difference - Full

Intersection - Full

Difference - Partial

Intersection - Partial

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):