Benchmark: Math.atan2(...arr) v. Math.atan2(arr[0], arr[1])

Script Preparation code:

var numbers = Array(100000).fill(null).map(x => [Math.random()*100, Math.random()*100])

Tests:

...arr
numbers.forEach(x => Math.atan2(...x));
arr[0], arr[1]
numbers.forEach(x => Math.atan2(x[0], x[1]));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
...arr
arr[0], arr[1]

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:93.0) Gecko/20100101 Firefox/93.0

Browser/OS: Firefox 93 on Windows

View result in a separate tab

Test name	Executions per second
...arr	16.6 Ops/sec
arr[0], arr[1]	31.6 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Definition**

The benchmark measures the performance difference between two ways of calling the `Math.atan2` function on an array of numbers:

1. `Math.atan2(...arr)`: This calls `Math.atan2` directly with all elements of the array.
2. `Math.atan2(arr[0], arr[1])`: This calls `Math.atan2` only with the first two elements of the array.

**Options Compared**

The benchmark compares the performance of these two approaches:

Pros and Cons:

* **Direct Call (`Math.atan2(...arr)`)**
	+ Pros: Can be more flexible, allows for arbitrary number of arguments.
	+ Cons: May incur overhead due to repeated function calls, can lead to slower execution if not optimized.
* **Indexed Call (`Math.atan2(arr[0], arr[1])`)**
	+ Pros: Typically faster due to optimized function call mechanisms, reduces overhead.
	+ Cons: Limited to only two arguments.

In general, direct calls are more flexible but might incur additional overhead. Indexed calls are often faster and more efficient, especially for common patterns like `Math.atan2` with two arguments.

**Library Usage**

None of the benchmark tests use a specific library, as they focus on native JavaScript functionality.

**Special JS Features or Syntax**

The benchmark does not explicitly test any special JavaScript features or syntax. However, it's worth noting that modern JavaScript engines often have optimizations and specializations for common patterns, which can affect performance in subtle ways.

**Alternatives**

If you were to create a similar benchmark, you might consider testing additional approaches, such as:

* Using `Array.prototype.map` instead of `forEach`
* Implementing the `Math.atan2` function from scratch
* Using a different library or framework for numerical computations

Keep in mind that benchmarks can be highly dependent on specific use cases and environments.

The benchmark result shows that the indexed call (`arr[0], arr[1]`) is faster than the direct call (`...arr`). This aligns with expectations, as the latter incurs additional overhead due to repeated function calls.

Related benchmarks:

Math.atan2(...arr) v. Math.atan2(arr[0], arr[1]) (version: 0)

Comparing performance of: ...arr vs arr[0], arr[1]

Created: 3 years ago by: Guest

Jump to the latest result

...arr

arr[0], arr[1]

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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