Benchmark: Set vs array indexOf vs array inclues

Script Preparation code:

var a = [
  '1',
  '2',
  '3',
  '4',
  '5',
  '6',
  '7',
  '8',
  '9',
  '10',
  '11',
  '12',
  '13',
  '14',
  '15',
  '16',
  '17',
  '18',
  '19',
  '20',
  '21',
  '22',
  '23',
  '24',
  '25',
  '26',
  '27',
  '28',
  '29',
  '30',
  'height',
  'width',
  'maxHeight',
  'maxWidth',
  'maxHeight',
  'minWidth',
  'color',
  'bg',
  'backgroundColor',
  'opacity',
  'm',
  'mt',
  'mb',
  'mr',
  'mr',
  'mx',
  'my',
  'p',
  'pt',
  'pb',
  'pr',
  'pl',
  'px',
  'py',
  'border',
  'boxShadow',
  'flex',
  'verticalAlign',
  'textAlign',
  'overflow',
  'display',
  'cursor'
];
var b = new Set(a)

Tests:

Array includes
return a.includes('cursor')
Set has
return b.has('mx')
Array indexOf
return a.indexOf('mx') >= 0

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array includes
Set has
Array indexOf

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

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

**Benchmark Definition**

The benchmark is designed to compare three different approaches for finding an element in arrays: `includes()`, `indexOf()` with equality comparison, and using a `Set` data structure. The purpose is to determine which approach is faster on average.

**Options Compared**

1. **Array `includes()`**: This method checks if a specified value (in this case, `'mx'`) exists in the array.
2. **Array `indexOf()` with equality comparison**: This method returns the index of the first occurrence of the specified value (`'mx'`) in the array. If the value is not found, it returns -1. In the benchmark code, we're comparing this to an equality check using `>= 0` to simulate a more complex condition.
3. **Set data structure**: We create a new `Set` object containing the elements of the original array and then use the `has()` method to check if `'mx'` is present in it.

**Pros and Cons**

1. **Array `includes()`**:
	* Pros: Simple, widely supported, and often used for quick checks.
	* Cons: May be slower for large arrays due to linear search.
2. **Array `indexOf()` with equality comparison**:
	* Pros: Can return the exact index of the element if found, making it useful for certain use cases.
	* Cons: Slower than `includes()` because it performs a linear search, and may return -1 even if the value is present in the array due to the inequality condition.
3. **Set data structure**:
	* Pros: O(1) lookup time on average, making it suitable for large datasets.
	* Cons: May require more memory and be less intuitive than using arrays or `includes()`.

**Library Usage**

In this benchmark, we're using the built-in JavaScript `Set` object, which is a data structure that automatically eliminates duplicate values. The `has()` method checks if a value is present in the set without having to iterate through all elements.

**Special JS Feature/Syntax**

None of the options used special JavaScript features or syntax in this benchmark. However, it's worth noting that the use of `Set` and its `has()` method relies on the internal implementation details of the JavaScript engine, which may change over time.

**Other Alternatives**

If you need to perform fast membership testing on large arrays, other alternatives include:

* Using a `SparseArray` or similar data structure, which can store only non-zero elements.
* Implementing your own binary search or hash-based lookup algorithm for arrays.
* Using external libraries like `lodash` or `fast-levelling`, which provide optimized versions of these operations.

Keep in mind that the choice of approach depends on the specific requirements and constraints of your use case.

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36

Browser/OS: Chrome 111 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array includes	26999734.0 Ops/sec
Set has	27333462.0 Ops/sec
Array indexOf	11786558.0 Ops/sec

Related benchmarks:

Set vs array indexOf vs array inclues (version: 0)

Comparing performance of: Array includes vs Set has vs Array indexOf

Created: one year ago by: Guest

Jump to the latest result

Array includes

Set has

Array indexOf

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):