Benchmark: SPlICE + UNSHIFT vs SORT (10000 items)

Script Preparation code:

var arr = [...Array(10000)].map((_,i) => i)

Tests:

SPLICE + UNSHIFT: array 10000 items; itemIndex - 10000
let newArr = [...arr] const item = 9999 const itemIndex = newArr.findIndex((x) => x === item) console.log('SPLICE + UNSHIFT [0] before', newArr[0]) console.log('SPLICE + UNSHIFT length before', newArr.length) newArr.splice(itemIndex, 1) newArr.unshift(item) console.log('SPLICE + UNSHIFT [0] after', newArr[0]) console.log('SPLICE + UNSHIFT length after', newArr.length)
SORT: array 10000 items; itemIndex - 10000
let newArr = [...arr] const item = 9999 const itemIndex = newArr.findIndex((x) => x === item) console.log('SORT [0] before', newArr[0]) console.log('SORT length before', newArr.length) newArr = newArr.sort((a, b) => { if (a === item) { return -1 } if (b === item) { return 1 } return 0 }) console.log('SORT [0] after', newArr[0]) console.log('SORT length after', newArr.length)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
SPLICE + UNSHIFT: array 10000 items; itemIndex - 10000
SORT: array 10000 items; itemIndex - 10000

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/135.0.0.0 Safari/537.36

Browser/OS: Chrome 135 on Windows

View result in a separate tab

Test name	Executions per second
SPLICE + UNSHIFT: array 10000 items; itemIndex - 10000	1967.4 Ops/sec
SORT: array 10000 items; itemIndex - 10000	827.3 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the explanation of the provided benchmark.

**Benchmark Overview**

The benchmark compares two approaches to find and remove an element from an array in JavaScript:

1. **SPLICE + UNSHIFT**: This approach uses the `splice()` method to remove the element at a specific index (`itemIndex`) and then inserts the target element (`item`) at the beginning of the array using the `unshift()` method.
2. **SORT**: This approach uses the `sort()` method with a custom comparison function to find and move the target element (`item`) to its correct position in the array.

**Comparison**

The benchmark tests these two approaches on an array of 10,000 elements. The test cases are designed to simulate the scenario where the target element is located at an index far from the beginning of the array (10000).

**Options Compared**

The benchmark compares the execution time of each approach:

1. **SPLICE + UNSHIFT**: This approach involves two operations:
	* `splice()` to remove the element at the specified index
	* `unshift()` to insert the target element at the beginning of the array
2. **SORT**: This approach uses a custom comparison function to sort the array and then finds the position of the target element.

**Pros and Cons**

1. **SPLICE + UNSHIFT**:
	* Pros: Efficient in terms of memory usage, as it only accesses elements around the specified index.
	* Cons: Can be slow if the array is large or the target index is far from the beginning, since it requires multiple iterations to move elements out of the way.
2. **SORT**:
	* Pros: Fast and efficient for large arrays, as it uses a efficient sorting algorithm.
	* Cons: May require additional memory to store the temporary sorted array.

**Library/Functionality Used**

1. `splice()`: A method that removes elements from an array at a specified index or within a specified range.
2. `unshift()`: A method that adds one or more elements to the beginning of an array.
3. `sort()`: A method that sorts the elements of an array in place and returns the sorted array.

**Special JS Feature/Syntax**

None mentioned in this benchmark.

**Other Alternatives**

1. **ITERATE**: Instead of using `splice()` and `unshift()`, you could iterate over the array to find and remove the target element.
2. **FILTER() + CONCAT()`: You could use the `filter()` method to create a new array with the target element removed, followed by concatenating the original array and the filtered array to create the final result.

Keep in mind that these alternatives may have different performance characteristics and memory usage compared to the benchmarked approaches.

Related benchmarks:

SPlICE + UNSHIFT vs SORT (10000 items) (version: 3)

Comparing performance of: SPLICE + UNSHIFT: array 10000 items; itemIndex - 10000 vs SORT: array 10000 items; itemIndex - 10000

Created: 3 years ago by: Registered User

Jump to the latest result

SPLICE + UNSHIFT: array 10000 items; itemIndex - 10000

SORT: array 10000 items; itemIndex - 10000

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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