Benchmark: atan2 vs acos - MeasureThat.net

Script Preparation code:

var N = 1000000;
var x = new Float32Array(N);
var y = new Float32Array(N);

for (var i = 0; i < N; ++i) {
    x[i] = 100 * Math.random();
    y[i] = 100 * Math.random();
}

Tests:

acos
var fn = Math.acos; for (var i = 0; i < N; ++i) { fn(x[i]/Math.sqrt(x[i]*x[i]+y[i]*y[i])); }
atan2
var fn = Math.atan; for (var i = 0; i < N; ++i) { fn(y[i], x[i]); }

Historical Performance Data aggregated from 52 community runs

Desktop Results:

Chrome 30 runs

atan2

381/s

acos

144/s

Fastest: atan2 (2.7x faster)

View exact numbers

✓ atan2: 381 ops/sec
• acos: 144 ops/sec

Firefox 22 runs

acos

2K/s

atan2

44/s

Fastest: acos (56.3x faster)

View exact numbers

✓ acos: 2,497 ops/sec
• atan2: 44 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
acos
atan2

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one month ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:150.0) Gecko/20100101 Firefox/150.0

Browser/OS: Firefox 150 on Windows

View result in a separate tab

acos

3K/s

atan2

59/s

View exact numbers

Test name	Executions per second
✓ acos	2,577 Ops/sec
atan2	59 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year 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 compares the performance of two functions: `Math.acos` and `Math.atan2`. The goal is to evaluate which function is faster when used in a specific numerical calculation.

**Options Compared**

Two options are compared:

1. **Using `Math.acos`**: This option uses the `acos` (inverse cosine) function, which takes only one argument.
2. **Using `Math.atan2`**: This option uses the `atan2` (inverse tangent, y/x) function, which takes two arguments.

**Pros and Cons**

* **Using `Math.acos`**:
	+ Pros: `acos` is generally a simple and fast function to compute. However, it's not designed for general-purpose inverse trigonometric calculations, so it may not be as accurate or robust as other options.
	+ Cons: It only takes one argument, which might limit its applicability in certain scenarios.
* **Using `Math.atan2`**:
	+ Pros: `atan2` is a more versatile and accurate function for inverse trigonometric calculations. However, it's also slightly slower than `acos` due to the additional complexity of handling both y/x coordinates.
	+ Cons: It requires two arguments (y/x), which might be less convenient in some cases.

**Library**

The benchmark uses the `Math` library, which is a built-in JavaScript library that provides various mathematical functions. In this case, it's used for the `acos` and `atan2` functions.

**Special JS Feature or Syntax**

This benchmark doesn't use any special JavaScript features or syntax beyond what's standard in modern JavaScript. However, it does rely on the `for` loop and the `Float32Array` constructor, which are both widely supported.

**Other Alternatives**

There are a few alternative approaches to implementing inverse trigonometric calculations:

1. **Using other libraries**: Other libraries like `mathjs`, `numjs`, or `fast-math` might provide more efficient or accurate implementations of these functions.
2. **Implementing from scratch**: One could write their own implementation of the `acos` and `atan2` functions in JavaScript, which would allow for more fine-grained control over performance and accuracy.
3. **Using SIMD instructions**: Modern CPUs often have SIMD (Single Instruction, Multiple Data) instructions that can accelerate certain mathematical operations. Implementing these functions using SIMD could potentially lead to better performance.

However, without additional context or knowledge of the specific requirements or constraints of the benchmark, it's difficult to suggest alternative approaches with confidence.

atan2 vs acos (version: 0)

Comparing performance of: `acos vs atan2`

Created: 5 years ago by: Guest

Go to the latest result

acos

atan2

Historical Performance Data aggregated from 52 community runs

Desktop Results:

Chrome 30 runs

Firefox 22 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

atan2 vs acos (version: 0)

Comparing performance of: acos vs atan2

Created: 5 years ago by: Guest

Go to the latest result

acos

atan2

Historical Performance Data aggregated from 52 community runs

Desktop Results:

Chrome 30 runs

Firefox 22 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `acos vs atan2`