Benchmark: JS find vs arr[indexOf ]

Script Preparation code:

var arr = [];
var i = 0;

while (i <= 1E5) arr[i] = i++;

Tests:

Array.find
const item = arr.find(item => item == 1E5);
Array.indexOf
const item = arr[arr.indexOf(1E5)];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.find
Array.indexOf

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared, and the pros and cons of different approaches.

**Benchmark Overview**

The benchmark measures the performance difference between using `Array.prototype.find()` and `Array.prototype.indexOf()` to retrieve an element from an array. The array is populated with consecutive integers from 0 to 100,000.

**Script Preparation Code**

The script preparation code creates an empty array `arr` and populates it with consecutive integers using a while loop:
```javascript
var arr = [];
var i = 0;
while (i <= 1E5) arr[i] = i++;
```
This code is executed before running each benchmark test case.

**Html Preparation Code**

The html preparation code is empty, which means no HTML elements are created to interact with the array. This might be due to the simple nature of the benchmark or because it's not necessary for this particular scenario.

**Benchmark Test Cases**

There are two test cases:

1. **Array.prototype.find()**
```javascript
const item = arr.find(item => item == 1E5);
```
This test case uses `Array.prototype.find()` to retrieve the element with a value of 100,000 from the array.

2. **Array.prototype.indexOf()**
```javascript
const item = arr[arr.indexOf(1E5)];
```
This test case uses `Array.prototype.indexOf()` to find the index of the element with a value of 100,000 in the array and then uses that index to retrieve the element.

**Library**

In this benchmark, no specific library is used besides the built-in JavaScript Array prototype methods. However, it's worth noting that some browsers may optimize or provide additional features for these methods, which could affect performance.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntax used in this benchmark that would require explanation beyond the standard Array methods.

**Pros and Cons of Different Approaches**

1. **Array.prototype.find()**
	* Pros:
		+ Returns the first element that satisfies the provided condition.
		+ Can be more readable and concise than using `indexOf()` and indexing into the array.
	* Cons:
		+ May perform slower in some cases due to its iterative nature.
2. **Array.prototype.indexOf()**
	* Pros:
		+ Can be faster for large arrays since it uses a linear search algorithm (although this is often mitigated by modern browser optimizations).
		+ Returns the index of the first occurrence, which can be useful if you need to access the element at that index.
	* Cons:
		+ Requires indexing into the array to retrieve the desired element.

**Other Considerations**

In general, for small arrays or simple use cases, `Array.prototype.find()` might be a better choice due to its readability and conciseness. However, for large arrays or performance-critical applications, `Array.prototype.indexOf()` might be a more suitable option due to its potential speed advantage.

Keep in mind that these are general guidelines, and actual performance may vary depending on the specific use case, browser, and JavaScript engine.

**Alternatives**

If you need alternative approaches, consider:

1. **Using `Array.prototype.every()` or `Array.prototype.some()`**: These methods can be used to filter arrays, but they might not offer the same performance benefits as `find()` or `indexOf()`.
2. **Implementing your own binary search algorithm**: For very large arrays, a custom binary search algorithm could provide optimal performance.
3. **Using a different data structure**: Depending on the specific requirements, using an array with a different data structure, such as a linked list or a tree-based data structure, might be more suitable for performance-critical applications.

Remember that each benchmark is unique, and it's essential to consider the specific use case, performance requirements, and limitations of the JavaScript engine being used.

Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36

Browser/OS: Chrome 121 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array.find	2299.2 Ops/sec
Array.indexOf	93637.0 Ops/sec

Related benchmarks:

JS find vs arr[indexOf ] (version: 0)

JS find vs indexOf

Comparing performance of: Array.find vs Array.indexOf

Created: 9 months ago by: Guest

Jump to the latest result

Array.find

Array.indexOf

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):