Benchmark: uniq vs groupBy - MeasureThat.net

HTML Preparation code:

<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.0/underscore.js"></script>

Script Preparation code:

  var data = _.range(10000).map(function(i) {
    return {
      number: Math.floor(Math.random() * 100) 
    }
  });

Tests:

groupBy
Object.keys(_(data).groupBy('number')).length
uniq
_.uniq(data.map(d => d.number)).length

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
groupBy
uniq

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's break down what is tested in this benchmark and explain the options compared, their pros and cons, and other considerations.

**What is being tested?**

The benchmark measures the performance difference between two approaches:

1. `groupBy`: This approach groups an array of objects by a common key (`number`) and returns an object with the grouped values.
2. `uniq`: This approach removes duplicates from an array of numbers and returns the length of the resulting array.

**Options compared**

The benchmark compares two different approaches to achieve these results:

1. Using the `groupBy` method from the Underscore.js library (`_`). This method is a built-in part of the library, which provides functional programming helpers.
2. Not using the `groupBy` method and instead creating an object to store the grouped values manually.

**Pros and Cons**

Here are some pros and cons of each approach:

**Using `_`.groupBy`:**

Pros:

* More concise code
* Built-in functionality in Underscore.js, which means it's already optimized for performance

Cons:

* Requires including another library (Underscore.js) in the benchmarking process
* May introduce additional overhead due to the library being loaded and parsed

**Manual grouping:**

Pros:

* No external library dependencies
* Can be faster because there's no overhead from loading a library

Cons:

* More verbose code
* Requires manual iteration over the data, which can lead to slower performance compared to using `groupBy`

**Other considerations**

* The benchmark assumes that the input data is an array of objects with a single key (`number`) that needs to be grouped. If this assumption doesn't hold true, the results may not be representative.
* The use of `Math.random()` to generate random numbers for testing purposes means that the results will vary between runs.

**Library: Underscore.js**

Underscore.js is a popular JavaScript library that provides functional programming helpers, including `groupBy`. Its purpose is to simplify common tasks and provide a more concise way of writing code. In this benchmark, it's used to provide the `groupBy` method, which is then compared to manual grouping.

**Special JS feature or syntax**

There are no special JS features or syntax mentioned in this benchmark. It only uses standard JavaScript syntax for array manipulation and object creation.

**Other alternatives**

If you wanted to implement manual grouping without using Underscore.js, you could use a simple loop to iterate over the data and create an object with grouped values. For example:
```javascript
var result = {};
data.forEach(function(d) {
  if (!result[d.number]) {
    result[d.number] = [];
  }
  result[d.number].push(d);
});
```
This approach would eliminate the need for including Underscore.js in the benchmarking process, but it's more verbose and may be slower due to manual iteration.

Related benchmarks:

uniq vs groupBy (version: 0)

Comparing performance of: groupBy vs uniq

Created: 4 years ago by: Guest

Jump to the latest result

groupBy

uniq

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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