Benchmark: toFixed vs Math.round() sd6f54sd6f54

Script Preparation code:

var someFloat = 0.123456789;

Tests:

toFixed(4) someFloat.toFixed(4); someFloat.t
+someFloat.toFixed(4);
Math.pow - Math.round
var nb = Math.pow(10, 4); (Math.round(someFloat*nb)/nb);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
toFixed(4) someFloat.toFixed(4); someFloat.t
Math.pow - Math.round

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model llama3.2:3b, generated 4 days ago):

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark definitions and explain what's being tested, compared, and their pros/cons.

**Benchmark Definition**

The first benchmark compares the performance of four different approaches to round or truncate a floating-point number:

1. `toFixed(4)` - Converts the number to a string with a fixed precision.
2. `(Math.round(*10000)/10000).toString()` - Rounds the number using `Math.round`, multiplies by 10,000, and then divides by 10,000 to preserve the original precision.
3. `Math.floor` (fast) - Truncates the number towards zero using `Math.floor`.
4. `new Math.trunc` (new feature) - Truncates the number towards zero using a new function introduced in ECMAScript 2020.

**Options Compared**

The benchmark compares the performance of these four approaches:

* Pros:
	+ `toFixed(4)` provides precise control over precision and formatting.
	+ `(Math.round(*10000)/10000).toString()` preserves the original precision but introduces unnecessary multiplication.
	+ `Math.floor` is a simple, fast, and widely supported approach (no new feature required).
	+ `new Math.trunc` offers improved performance on modern browsers using the new function (note: not all JavaScript engines support this feature yet).
* Cons:
	+ `(Math.round(*10000)/10000).toString()` has unnecessary multiplication and may be slower than other approaches.
	+ `toFixed(4)` can be slower due to the string conversion.

**Library and Special JS Features**

The test uses no external libraries or special JavaScript features beyond the ones already mentioned (e.g., modern browsers' support for `new Math.trunc`). However, it's worth noting that some browsers might have slightly different performance characteristics for these operations.

**Other Alternatives**

Alternative approaches to rounding or truncating numbers in JavaScript include:

* Using a library like [BigInt](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt) for precise arithmetic and rounding.
* Implementing custom rounding functions using bitwise operations (e.g., `>>>` for unsigned integer division).
* Utilizing specialized libraries or frameworks that optimize floating-point arithmetic, such as [fast-math](https://github.com/mvdanielly/fast-math).

**Test Case Breakdown**

The provided test cases are designed to exercise specific variations of the rounding and truncation functions:

1. `toFixed(4) someFloat.toFixed(4); someFloat.t`:
	* Compares performance of consecutive calls to `toFixed(4)` with a single call to `someFloat`.
2. `Math.pow - Math.round`:
	* Tests the performance impact of using `Math.pow` on a large exponent compared to simply multiplying by 10,000.

These test cases help isolate the effects of specific rounding and truncation approaches, allowing for more accurate benchmarking and comparison of their relative performances.

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
toFixed(4) someFloat.toFixed(4); someFloat.t	3558038.0 Ops/sec
Math.pow - Math.round	3849544.0 Ops/sec

Related benchmarks:

toFixed vs Math.round() sd6f54sd6f54 (version: 0)

Comparing performance of: toFixed(4) vs toPrecision(4).toString() vs (Math.round(*10000)/10000).toString() vs Math.floor fast vs the new Math.trunc

Comparing performance of: toFixed(4) someFloat.toFixed(4); someFloat.t vs Math.pow - Math.round

Created: 10 months ago by: Guest

Jump to the latest result

toFixed(4) someFloat.toFixed(4); someFloat.t

Math.pow - Math.round

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model llama3.2:3b, generated 4 days ago):