Benchmark: Benchmark Reduce vs Concat vs Join

Tests:

Join
const testArray = [[1, 2, 3], [4, 5, 6], [7, 8, 9, 10, 11]] const newTestArray = testArray.join().split(",");
Concat
const testArray = [[1, 2, 3], [4, 5, 6], [7, 8, 9, 10, 11]] const newTestArray = [].concat(...testArray)
Reduce
const testArray = [[1, 2, 3], [4, 5, 6], [7, 8, 9, 10, 11]] const newTestArray = testArray.reduce((prev, next) => prev.concat(next))
Raw
const testArray = [[1, 2, 3], [4, 5, 6], [7, 8, 9, 10, 11]] var newTestArray = new Array(); for (var x = 0; x < testArray.length; x++){ for (var y = 0; y < testArray[x].length; y++){ newTestArray.push(testArray[x][y]) } }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Join
Concat
Reduce
Raw

Fastest: N/A

Slowest: N/A

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/115.0.0.0 Safari/537.36

Browser/OS: Chrome 115 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Join	1575959.0 Ops/sec
Concat	12413136.0 Ops/sec
Reduce	8499130.0 Ops/sec
Raw	11381336.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

The benchmark you provided measures the performance of three different methods for flattening an array of arrays: `join()`, `concat()`, and `reduce()`. Additionally, it includes a "Raw" test case that uses a traditional loop to flatten the array.

**Tested Options**

1. **`join()`**: This method concatenates all elements in the array into a single string using commas as separators.
2. **`concat()`**: This method returns a new array containing all elements from each sub-array.
3. **`reduce()`**: This method applies a callback function to each element in the array, reducing it to a single value.
4. **Raw**: A traditional loop-based approach that pushes each element into a new array.

**Pros and Cons of Each Approach**

1. **`join()`**:
	* Pros: Simple and concise code, easy to read.
	* Cons: Can be slow for large arrays due to string concatenation overhead.
2. **`concat()`**:
	* Pros: Fast and efficient, suitable for large arrays.
	* Cons: Creates a new array on each execution, potentially leading to memory usage issues.
3. **`reduce()`**:
	* Pros: Flexible and powerful, can be used for various operations beyond flattening.
	* Cons: Requires an understanding of the callback function, which can add complexity.
4. **Raw**:
	* Pros: Control over the flattening process, no external functions or libraries required.
	* Cons: More verbose code, may lead to errors if not implemented correctly.

**Library and Syntax Used**

In this benchmark, the `reduce()` method uses a callback function (`prev.concat(next)`) to flatten the array. The `concat()` method directly concatenates arrays using the spread operator (`...`). There is no explicit library or syntax used in these examples.

**Other Considerations**

When choosing between these methods, consider the following:

* **Memory usage**: If you're working with large datasets, `concat()` might be a better choice due to its ability to create a new array on each execution.
* **Code readability and maintainability**: For small arrays or simple use cases, `join()` might be sufficient. However, for larger datasets or complex flattening operations, `reduce()` offers more flexibility and control.
* **Performance**: In general, `concat()` is faster than `join()`, while `reduce()` can be slower due to the callback function overhead.

**Alternatives**

If you're looking for alternative methods to flatten arrays in JavaScript, consider:

1. **`flat()`**: A newer method introduced in ECMAScript 2019 that flattens an array of arrays into a one-dimensional array.
2. **`flatMap()`**: Another new method that transforms each element of an array into an array and then flattens the resulting array.
3. **External libraries or frameworks**: Depending on your specific requirements, you might consider using external libraries like Lodash or Ramda, which provide optimized and reusable functions for array manipulation.

Remember to always evaluate performance, readability, and maintainability when choosing a method for flattening arrays in JavaScript.

Related benchmarks:

Benchmark Reduce vs Concat vs Join (version: 0)

Comparing performance of: Join vs Concat vs Reduce vs Raw

Created: one year ago by: Guest

Jump to the latest result

Join

Concat

Reduce

Raw

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):