Benchmark: roudning - MeasureThat.net

Script Preparation code:

var nums = Array.from({ length: 10000 }, () => (Math.random() * 2 - 1) * 10000)
var sum = 0

Tests:

weird round
for (let i = 0; i < nums.length; i++) sum += (nums[i] + (nums[i] > 0 ? 0.5 : -0.5)) << 0
Math.round
for (let i = 0; i < nums.length; i++) sum += Math.round(nums[i])

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
weird round
Math.round

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

I'll break down the provided JSON data and explain what's being tested, the different approaches compared, their pros and cons, and other considerations.

**Benchmark Definition**

The provided JSON data represents a JavaScript microbenchmark named "rouding". It defines two benchmarking tests:

1. **"weird round"**: This test measures the performance of rounding numbers using a custom implementation.
2. **"Math.round"`: This test measures the performance of using the built-in `Math.round()` function.

**Benchmark Preparation Code**

The script preparation code for both tests is similar and generates an array of 10,000 random integers between -10000 and 10000.

```javascript
var nums = Array.from({ length: 10000 }, () => (Math.random() * 2 - 1) * 10000)
var sum = 0
```

This code creates an array `nums` with 10,000 random integers. It then initializes a variable `sum` to zero.

**Html Preparation Code**

There is no HTML preparation code provided for this benchmark.

**Test Cases**

The two test cases are identical except for the implementation used for rounding:

1. **"weird round"`**: This test uses a custom implementation that rounds numbers using a bitwise shift operation.
```javascript
for (let i = 0; i < nums.length; i++) sum += (nums[i] + (nums[i] > 0 ? 0.5 : -0.5)) << 0
```
This implementation is likely designed to test the performance of the browser's rounding algorithm.

2. **"Math.round"`**: This test uses the built-in `Math.round()` function.
```javascript
for (let i = 0; i < nums.length; i++) sum += Math.round(nums[i])
```
This implementation tests the performance of using the built-in rounding function.

**Library and Purpose**

Neither of these implementations uses any external libraries. However, if we were to compare the performance of these tests, it's likely that a library like `BigInt` or `Decimal.js` might be used for more precise arithmetic.

**Special JS Features or Syntax**

The custom implementation in "weird round" uses a bitwise shift operation (`<< 0`) to round numbers. This is a unique and interesting approach that takes advantage of JavaScript's bitwise operations. It's likely designed to test the performance of browser's rounding algorithm.

**Pros and Cons**

1. **Custom Implementation ("weird round")**:
	* Pros: Allows for precise control over the rounding process, which can be useful in certain applications.
	* Cons: May introduce additional overhead or complexity compared to using built-in functions like `Math.round()`.
2. **Built-in `Math.round()` Function**:
	* Pros: Easy to use and well-tested, with good performance on most browsers.
	* Cons: May not provide the same level of precision as a custom implementation.

**Other Considerations**

When comparing these tests, it's essential to consider factors like:

* Performance: How fast does each test execute?
* Accuracy: Do the results match expectations or known values?
* Code simplicity: Which implementation is easier to understand and maintain?

In this case, both tests are designed to measure performance rather than accuracy.

**Alternatives**

If you were to create similar benchmarks for other rounding algorithms or implementations, you might consider:

* Using `BigInt` or `Decimal.js` for more precise arithmetic.
* Implementing rounding algorithms like "banker's rounding" or "round half to even".
* Creating benchmark tests that compare the performance of different browsers or versions.

I hope this explanation helps!

Related benchmarks:

roudning (version: 0)

Comparing performance of: weird round vs Math.round

Created: 2 years ago by: Guest

Jump to the latest result

weird round

Math.round

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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