Benchmark: merge arrays 2 - MeasureThat.net

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var MyArr = Array.from({length: 40}, () => Math.floor(Math.random() * 40));
var MyArr2 = Array.from({length: 40}, () => Math.floor(Math.random() * 40));
var myCopy = null;

Tests:

spread operator
myCopy = [...MyArr, ...MyArr2]
concat
myCopy = MyArr.concat(MyArr2)
flat
myCopy = [MyArr, MyArr2].flat()
push
myCopy = MyArr.push(MyArr2)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
spread operator
concat
flat
push

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

MeasureThat.net is a platform where users can create and run JavaScript microbenchmarks to compare the performance of different approaches. In this case, we have a benchmark that tests four different ways to merge two arrays.

**Script Preparation Code**

The script preparation code generates two random arrays of 40 elements each using `Array.from()` and assigns them to variables `MyArr` and `MyArr2`. The variable `myCopy` is initialized as null.

**Html Preparation Code**

The html preparation code includes a reference to the Lodash library, which provides utility functions for JavaScript. In this case, it's used to enable the spread operator (`...`) feature in JavaScript.

**Individual Test Cases**

There are four test cases:

1. **Spread Operator**: `myCopy = [...MyArr, ...MyArr2]`
This test case uses the spread operator to merge the two arrays.
```javascript
// Lodash library is required for this syntax
var myCopy = [...MyArr, ...MyArr2];
```

**Pros and Cons**

The spread operator provides a concise way to merge arrays, but it can also lead to performance issues if not used carefully. In this case, the benchmark will test whether the spread operator is faster than other approaches.

* **Cons**: The spread operator may introduce unnecessary overhead due to the creation of new arrays.
* **Pros**: The spread operator provides a concise and expressive way to merge arrays.

2. **Concatenation**: `myCopy = MyArr.concat(MyArr2)`
This test case uses the `concat()` method to merge the two arrays.
```javascript
var myCopy = MyArr.concat(MyArr2);
```

**Pros and Cons**

The concatenation approach is a simple way to merge arrays, but it can lead to performance issues if not used carefully. In this case, the benchmark will test whether concatenation is faster than other approaches.

* **Cons**: Concatenation creates new arrays, which can lead to unnecessary memory allocation.
* **Pros**: Concatenation is a straightforward and widely supported method for merging arrays.

3. **Flat() Method**: `myCopy = [MyArr, MyArr2].flat()`
This test case uses the `flat()` method to merge the two arrays.
```javascript
var myCopy = [MyArr, MyArr2].flat();
```

**Pros and Cons**

The flat() method is a relatively new feature in JavaScript (introduced in ECMAScript 2019). While it provides a concise way to flatten arrays, its performance might be affected by the browser's implementation.

* **Cons**: The flat() method may not be supported in older browsers or have poor performance.
* **Pros**: The flat() method is a concise and expressive way to flatten arrays.

4. **Push Method**: `myCopy = MyArr.push(MyArr2)`
This test case uses the `push()` method to merge the two arrays.
```javascript
var myCopy = MyArr.push(MyArr2);
```

**Pros and Cons**

The push() method is not a standard way to merge arrays, as it modifies the original array.

* **Cons**: The push() method modifies the original array, which can lead to unexpected behavior if used carelessly.
* **Pros**: None, except for potentially being faster due to fewer function calls.

**Other Considerations**

When choosing an approach, consider the following factors:

* Performance: The spread operator and concatenation methods create new arrays, while the flat() method modifies the original array.
* Memory usage: Concatenation creates multiple intermediate arrays, which can lead to increased memory usage.
* Browser support: Make sure to test the benchmark in various browsers to ensure compatibility.

**Alternatives**

If you need to merge arrays frequently, consider using a library like Lodash or a dedicated array merging library. Alternatively, if performance is critical, consider using a more optimized approach, such as using native Web Workers or leveraging hardware acceleration.

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser/OS: Chrome 120 on Windows

View result in a separate tab

Test name	Executions per second
spread operator	3675925.8 Ops/sec
concat	4132704.0 Ops/sec
flat	351101.8 Ops/sec
push	6686507.5 Ops/sec

Related benchmarks:

merge arrays 2 (version: 0)

Comparing performance of: spread operator vs concat vs flat vs push

Created: one year ago by: Guest

Jump to the latest result

spread operator

concat

flat

push

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):