Benchmark: uniq indexOf vs lodash uniq

Script Preparation code:

var unique = (value, index, self) => {
    return self.indexOf(value) === index;
};

var items = [];
for (i = 0; i < 1000000; i++) {
    items.push(Math.floor(Math.random() * 100));
}

Tests:

ld uniq
_.uniq(items)
index of
items.filter(unique);
set
[...new Set(items)];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
ld uniq
index of
set

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Linux

View result in a separate tab

Test name	Executions per second
ld uniq	61.6 Ops/sec
index of	33.6 Ops/sec
set	58.4 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and benchmark results.

**Benchmark Definition**

The `Script Preparation Code` section defines two small JavaScript functions:

1. `unique`: This is an arrow function that takes three arguments: `value`, `index`, and `self`. It returns `true` if the `value` is found at its current `index` in the array (`self.indexOf(value) === index`). This function is not directly used in the benchmark but serves as a starting point for creating a custom filter.
2. The variable `items` is an array of 1,000,000 random integers.

The `Html Preparation Code` section is empty, which means there's no additional setup required for the benchmark.

**Individual Test Cases**

There are three test cases:

1. `_.uniq(items)`: This test case uses Lodash's `uniq` function to remove duplicates from the `items` array.
2. `items.filter(unique)` : This test case filters the `items` array using a custom filter function (`unique`) that we defined earlier.
3. `[...new Set(items)]`: This test case converts the `items` array to an array of unique values using the spread operator and a new `Set`.

**Comparison of Approaches**

1. Lodash's `uniq`:
	* Pros: Efficient, reliable, and widely tested.
	* Cons: Adds external dependency (Lodash), might not be suitable for all use cases.
2. Custom filter function (`unique`):
	* Pros: Tailored to the specific problem, no external dependencies.
	* Cons: May not be as efficient or reliable as Lodash's `uniq`, requires more code and testing effort.
3. Using a `Set`:
	* Pros: Simple, efficient, and widely supported.
	* Cons: Can be slower than Lodash's `uniq` for very large datasets.

**Special JS Features**

None are explicitly mentioned in the benchmark definition or test cases. However, using Lodash requires understanding its API and how to import it (e.g., `import _ from 'lodash';`) since it's not a built-in JavaScript function.

**Other Alternatives**

If you don't want to use Lodash, you could:

1. Use the Array.prototype.filter() method with a custom callback function.
2. Implement a set data structure using a custom array or object.
3. Utilize other library functions for unique value extraction (e.g., `Set` or `Map`).

Keep in mind that each approach has its trade-offs and might not be suitable for all scenarios.

In this benchmark, Lodash's `uniq` appears to be the fastest method, but it's essential to understand the pros and cons of each approach before choosing one.

Related benchmarks:

uniq indexOf vs lodash uniq (version: 0)

Comparing performance of: ld uniq vs index of vs set

Created: 4 years ago by: Registered User

Jump to the latest result

ld uniq

index of

set

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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