Benchmark: difference 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 arr1 = [];
for(let i = 0; i < 100; i++) {
  arr1.push('' + i);
}

var arr2 = [];
for(let i = 49; i >= 0; i--) {
  arr2.push('' + i);
}

Tests:

_difference
const finalArray = _.difference(arr1, arr2)
Set/Filter
const set2 = new Set([...arr2]); const finalArray = arr1.filter(value => !set2.has(value));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
_difference
Set/Filter

Fastest: N/A

Slowest: N/A

Latest run results:

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

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Let's break down the provided benchmark and its test cases.

**Benchmark Overview**

MeasureThat.net is a website where users can create and run JavaScript microbenchmarks to compare different approaches for achieving a specific goal. The benchmark in question is comparing two methods: using the `difference` function from the Lodash library, and using a Set to filter out elements from an array.

**Script Preparation Code**

The script preparation code generates two arrays: `arr1` and `arr2`. `arr1` contains 100 elements starting from 0 and incrementing by 1 (using `var arr1 = []; for(let i = 0; i < 100; i++) { ... }`). `arr2` contains the same number of elements, but in reverse order, starting from 99 and decrementing by 1 (using `for(let i = 49; i >= 0; i--) { ... }`).

**Html Preparation Code**

The HTML preparation code includes a reference to Lodash version 4.17.5, which is used as the library for the `_difference` test case.

**Test Cases**

There are two individual test cases:

1. **_difference**: This test case uses the `difference` function from Lodash to find the elements that exist in `arr1` but not in `arr2`. The benchmark code is: `const finalArray = _.difference(arr1, arr2)`.
2. **Set/Filter**: This test case uses a Set to filter out elements from `arr1` that are present in `arr2`. The benchmark code is: `const set2 = new Set([...arr2]); const finalArray = arr1.filter(value => !set2.has(value))`.

**Comparison of Approaches**

The two approaches differ in their performance characteristics:

* **_difference**: This approach uses a library function that performs a set operation between the two arrays. The Lodash `difference` function is optimized for performance and has a relatively low overhead.
* **Set/Filter**: This approach uses a Set to store elements from `arr2`, and then filters out elements from `arr1` using the `has` method of the Set. This approach requires creating a new Set, which can be slower than using a library function.

**Pros and Cons**

* **_difference**:
	+ Pros: Uses an optimized library function that is likely to be faster.
	+ Cons: Requires including Lodash in the benchmark code, which may add overhead.
* **Set/Filter**:
	+ Pros: Does not require including any external libraries, making it a more self-contained approach.
	+ Cons: Can be slower due to the creation of a new Set and the `has` method calls.

**Other Considerations**

* **Scalability**: Both approaches may become slower as the size of the input arrays increases. However, the `_difference` approach is likely to remain faster due to its optimized library function.
* **Memory Usage**: The `_difference` approach uses less memory since it only stores a reference to the Lodash function and the two input arrays. The `Set/Filter` approach requires creating a new Set, which can increase memory usage.

**Alternative Approaches**

Other approaches that could be used instead of the `_difference` and `Set/Filter` methods include:

* Using a manual implementation of set difference or filtering, without relying on a library function.
* Using other data structures, such as a Map or a tree-based data structure, to optimize the filtering process.
* Using a different programming language or paradigm that is optimized for array operations.

It's worth noting that the choice of approach ultimately depends on the specific requirements and constraints of the project. The MeasureThat.net benchmark provides a useful comparison between two popular approaches, but other considerations may need to be taken into account when selecting an optimal solution.

Related benchmarks:

difference vs Set (version: 0)

Comparing performance of: _difference vs Set/Filter

Created: 3 years ago by: Guest

Jump to the latest result

_difference

Set/Filter

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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