Benchmark: Array.splice vs Array.filter V223

HTML Preparation code:

<script>
  const array = ["first","second","third","asdawd","cxzcas","ljjjln","dfh93fsad9","asdfeh5","dsag442","gdsgds","fdsfrhdgr"];
</script>

Script Preparation code:

function spliceIt(array){
	const indexToRemove = array.findIndex((el) => el === "asdfeh5")
  array.splice(indexToRemove, 1);
}

function filterIt(array){
  array = array.filter((el) => el !== "asdfeh5");
}

Tests:

Splice It
spliceIt(array, 5);
filter It
filterIt(array, 5);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Splice It
filter It

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:147.0) Gecko/20100101 Firefox/147.0

Browser/OS: Firefox 147 on Linux

View result in a separate tab

Test name	Executions per second
Splice It	16800106.0 Ops/sec
filter It	94693648.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in the provided JSON benchmark.

**Benchmark Definition**

The website is testing two approaches for removing an element from an array:

1. `Array.splice()`: This method modifies the original array by removing the specified element at the given index.
2. `Array.filter()`: This method creates a new array with all elements that pass the test implemented by the provided function.

**Options Compared**

The benchmark is comparing the performance of these two approaches when removing an element from an array:

* `spliceIt(array, 5)`: This calls `splice()` on the original array, removing the 6th element (index 5).
* `filterIt(array, 5)`: This uses `filter()` to create a new array with all elements except the one at index 5.

**Pros and Cons**

**`Array.splice()`**:

Pros:

* Modifies the original array, which can be more efficient for large datasets.
* Can be faster since it only needs to update a single element's position in the array.

Cons:

* Returns the removed element, which can be unnecessary if you don't need it back.
* Can cause issues with array indexing and bounds checking if not used carefully.

**`Array.filter()`**:

Pros:

* Creates a new array with the desired elements, leaving the original array unchanged.
* Allows for more control over the filtering process using a custom function.

Cons:

* Requires creating a new array, which can be memory-intensive for large datasets.
* Can be slower since it needs to create and copy the new array.

**Other Considerations**

In JavaScript, `Array.prototype.splice()` is generally faster than `Array.prototype.filter()`, especially when removing elements from the beginning of the array. This is because `splice()` only needs to update a single element's position in the array, whereas `filter()` creates a new array by iterating over all elements and applying the filtering function.

In contrast, `filter()` can be more useful when working with large datasets or when you need to preserve the original array and create a new one based on specific conditions.

**Library Usage**

There is no explicit library usage in this benchmark. However, some JavaScript engines may use their own internal arrays or optimized implementations of these methods, which could affect performance.

**Special JS Feature or Syntax**

None mentioned in this benchmark.

Now that we've broken down the benchmark, let's discuss alternative approaches:

1. **Using `Array.prototype.map()` instead of `filter()`**: This can be a good alternative when you need to create a new array with transformed elements, rather than just filtering out unwanted ones.
2. **Using `slice()` and `concat()`**: These methods can be used to remove or filter elements from an array in different ways, depending on your specific use case.
3. **Using a custom iterator or generator function**: If you need more control over the iteration process or want to optimize performance, using a custom iterator or generator function can be an option.

Keep in mind that each approach has its pros and cons, and the best choice depends on your specific requirements and use case.

Related benchmarks:

Array.splice vs Array.filter V223 (version: 0)

Test a speed difference between these 2 approaches

Comparing performance of: Splice It vs filter It

Created: one year ago by: Guest

Jump to the latest result

Splice It

filter It

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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