Benchmark: round vs trunc vs floor

Tests:

trunc
Math.trunc(13.37) Math.trunc(13.67)
round
Math.round(13.37) Math.round(13.67)
floor
Math.floor(13.37) Math.floor(13.67)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
trunc
round
floor

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 21 days ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:149.0) Gecko/20100101 Firefox/149.0

Browser/OS: Firefox 149 on Linux

View result in a separate tab

Test name	Executions per second
trunc	551447616.0 Ops/sec
round	567068864.0 Ops/sec
floor	545512640.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the explanation of what's tested on the provided JSON and explore the different options being compared.

**What is being tested?**

The benchmark measures the performance difference between three rounding functions in JavaScript: `Math.trunc`, `Math.round`, and `Math.floor`. Each function is tested with two input values, `13.37` and `13.67`.

**Options being compared:**

1. **Trunc (Toward Zero)**: Rounds a number to the nearest integer, towards zero.
2. **Round**: Rounds a number to the nearest integer, using the standard rounding mode (up in case of decimal 0.5).
3. **Floor**: Rounds a number down to the nearest integer.

**Pros and Cons:**

*   **Trunc**: Pros - generally faster than Round and Floor due to fewer arithmetic operations. Cons - rounds towards zero, which may not be suitable for all use cases.
*   **Round**: Pros - provides more accurate results when rounding 0.5 decimal places. Cons - generally slower than Trunc and Floor due to additional arithmetic operations.
*   **Floor**: Pros - rounds down to the nearest integer, ensuring a smaller result. Cons - may not be suitable for all use cases where rounding up is desired.

**Library and purpose:**

The `Math` library provides these three rounding functions:

*   **Math.trunc()**: Returns the largest (for positive numbers) or smallest (for negative numbers) integer less than or equal to a given number.
*   **Math.round()**: Returns the closest integer to a given number, either rounding up or down depending on the value of the fractional part of that number.
*   **Math.floor()**: Returns the largest integer not greater than a given number.

**Special JS feature or syntax:**

The benchmark doesn't use any special JavaScript features or syntax. It's purely focused on testing the performance difference between these three rounding functions.

**Other alternatives:**

If you need to round numbers in JavaScript, other alternatives include:

*   Using the `toFixed()` method with a string representation of the decimal places.
*   Implementing custom rounding logic using bitwise operations or arithmetic expressions.
*   Utilizing third-party libraries that offer optimized rounding algorithms.

For example, you can use the `toFixed()` method to round numbers:
```javascript
let number = 13.37;
let roundedNumber = Math.round(number * 100) / 100; // rounds to two decimal places
```
However, keep in mind that this approach may not be as efficient as using built-in functions like Trunc, Round, or Floor.

In summary, the benchmark measures the performance difference between three rounding functions in JavaScript: `Math.trunc`, `Math.round`, and `Math.floor`. Understanding their differences and trade-offs can help you make informed decisions about which function to use depending on your specific requirements.

Related benchmarks:

round vs trunc vs floor (version: 0)

Comparing performance of: trunc vs round vs floor

Created: 8 years ago by: Guest

Jump to the latest result

trunc

round

floor

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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