Benchmark: Spacing numbers every 3 digits

Tests:

Using map+reverse+join
"112345678".split("").reverse().map((x,i)=>{ if((i + 1) % 3 === 0){ return " "+x; } else { return x; } }).reverse().join("").trim();
Using reduce
"12345678" .split("") .reverse() .reduce((acc, cur, i) => (((i + 1) % 3 === 0 ? ' ' : '') + cur + acc) , "").trim();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Using map+reverse+join
Using reduce

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested.

**Benchmark Overview**

The benchmark measures how efficiently JavaScript can process a string by splitting it into individual characters, reversing the order, and then spacing every 3rd character with a space. The two test cases use different approaches to achieve this:

1. **Using map+reverse+join**: This approach uses the `map()` method to create a new array of spaced characters, reverses the array using `reverse()`, and then joins the characters back into a string using `join()`.
2. **Using reduce**: This approach uses the `reduce()` method to iterate over the reversed array and build the spaced string.

**Options Compared**

The two test cases compare the performance of these two different approaches:

* **map+reverse+join**
	+ Pros:
		- Easier to read and understand for developers familiar with array methods.
	+ Cons:
		- May incur additional overhead due to creating an intermediate array.
* **reduce**
	+ Pros:
		- Can be more efficient since it avoids creating an intermediate array.
	+ Cons:
		- Requires knowledge of the `reduce()` method and its callback function.

**Other Considerations**

Both approaches have similar performance characteristics, but the `map+reverse+join` approach may be slightly slower due to the additional overhead of creating an intermediate array. However, the actual performance difference is likely to be small, and other factors like JavaScript engine optimizations, hardware, and browser versions can significantly impact the results.

**Library Usage**

There doesn't appear to be any libraries used in these test cases. The `map()`, `reverse()`, `join()`, and `reduce()` methods are built-in JavaScript methods.

**Special JS Features or Syntax**

None of the provided benchmark definitions contain special JavaScript features or syntax. They use only standard JavaScript constructs.

**Alternative Approaches**

Other possible approaches to achieve this spacing task could be:

* Using a regular expression with the `match()`, `join()`, and `replace()` methods.
* Utilizing a library like `lodash` with its `range()` and `map()` functions.
* Implementing a custom iteration loop using `for...of` or `while` loops.

However, these alternative approaches might not be as concise or readable as the original `map+reverse+join` and `reduce` methods.

Latest run results:

Run details: (Test run date: 6 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0

Browser/OS: Firefox 62 on Linux

View result in a separate tab

Test name	Executions per second
Using map+reverse+join	1751516.1 Ops/sec
Using reduce	2857579.8 Ops/sec

Related benchmarks:

Spacing numbers every 3 digits (version: 0)

Comparing performance of: Using map+reverse+join vs Using reduce

Created: 6 years ago by: Guest

Jump to the latest result

Using map+reverse+join

Using reduce

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):