Benchmark: lodash.round VS Math.round with precision

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var x = Math.random() * 100;

Tests:

Round floating number using lodash round function
for (var i = 0; i < 1000; i++) { _.round(x, 2); }
Round floating number using toFixed()
for (var i = 0; i < 1000; i++) { Number(x.toFixed(2)); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Round floating number using lodash round function
Round floating number using toFixed()

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36

Browser/OS: Chrome 122 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Round floating number using lodash round function	1649.9 Ops/sec
Round floating number using toFixed()	2674.4 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and its results.

**Benchmark Overview**

The benchmark compares two approaches to rounding numbers in JavaScript: Lodash's `round` function and the native `toFixed` method.

**Lodash's Round Function**

Lodash is a popular utility library for JavaScript. Its `round` function takes two arguments: the number to be rounded, and the precision (number of decimal places). The function returns the rounded value as a string.

In this benchmark, Lodash's `round` function is used with a precision of 2.

**Native toFixed Method**

The native `toFixed` method in JavaScript rounds a number to a specified number of decimal places. It takes two arguments: the number to be rounded, and the number of decimal places.

In this benchmark, the native `toFixed` method is used with a precision of 2.

**Pros and Cons**

Both approaches have their pros and cons:

* **Lodash's Round Function**
	+ Pros:
		- Can handle negative numbers and zero correctly.
		- Allows for customization of rounding mode (e.g., "round to even" or "round to nearest").
	+ Cons:
		- May be slower than native methods due to the overhead of a JavaScript library.
* **Native toFixed Method**
	+ Pros:
		- Generally faster than Lodash's `round` function.
		- More efficient use of memory, as it doesn't require creating an additional string object.
	+ Cons:
		- Can be less intuitive for developers who are not familiar with this method.

**Other Considerations**

* The benchmark uses a random input value (`x`) to avoid JavaScript engine optimizations. This ensures that the results are consistent across different browsers and engines.
* The `use strict` mode is not specified in the benchmark, which means it will default to non-strict mode. If you want to test with `use strict`, you'll need to add it explicitly to your script.

**Latest Benchmark Results**

The latest benchmark results show that:

* Chrome 122 on Mac OS X 10.15.7 favors the native `toFixed` method, executing 1034.35 times more than Lodash's `round` function.
* The device platform (Desktop) and operating system (Mac OS X 10.15.7) are specified in the results.

**Other Alternatives**

If you're interested in exploring other rounding methods or libraries, here are a few alternatives:

* For custom rounding modes: You can use the `Number.EPSILON` constant to calculate the smallest representable value of a number.
* For decimal arithmetic: Libraries like Decimal.js or Big.js provide high-precision arithmetic and rounding options.
* For testing purposes: You can also consider using libraries like Benchmark.js, which provides a more comprehensive benchmarking framework.

Related benchmarks:

lodash.round VS Math.round with precision (version: 0)

Compare round lodash function vs javascript native toFixed() function. use random input to avoid js engine optimisation

Comparing performance of: Round floating number using lodash round function vs Round floating number using toFixed()

Created: 2 years ago by: Guest

Jump to the latest result

Round floating number using lodash round function

Round floating number using toFixed()

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):