Benchmark: lodash.round VS toFixed() VS toFixed() and parseFloat

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 = 5.236;

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++) { x.toFixed(2); }
Round floating number using toFixed() and parseFloat
for (var i = 0; i < 1000; i++) { parseFloat(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()
Round floating number using toFixed() and parseFloat

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.36 Edg/147.0.0.0

Browser/OS: Chrome 147 on Windows

View result in a separate tab

Test name	Executions per second
Round floating number using lodash round function	1233.9 Ops/sec
Round floating number using toFixed()	6663.3 Ops/sec
Round floating number using toFixed() and parseFloat	4302.5 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 JSON and explain what's being tested, compared, and the pros/cons of each approach.

**Benchmark Definition**

The benchmark is comparing three approaches to rounding floating-point numbers:

1. `_.round(x, 2)` using the Lodash library
2. `x.toFixed(2)`
3. `parseFloat(x.toFixed(2))`

**Lodash Library**

The Lodash library is a popular JavaScript utility library that provides a wide range of functions for tasks such as array manipulation, string normalization, and more. The `round` function in particular is used to round numbers to a specified number of decimal places.

**Options Comparison**

Here's a brief comparison of the three approaches:

1. **`.round(x, 2)` (Lodash)**: This approach uses the Lodash library's `round` function to round the floating-point number `x` to 2 decimal places. The pros include:
	* A simple and concise way to round numbers.
	* Built-in rounding behavior with no need for manual calculation.
	Cons:
	* Requires the inclusion of the Lodash library in the test code, which may not be desirable for all projects.
	* May have a slight performance overhead due to the function call.
2. **`x.toFixed(2)`**: This approach uses the `toFixed()` method on the `x` variable to format it as a string with 2 decimal places. The pros include:
	* Native JavaScript implementation, eliminating the need for an external library.
	* Fast and efficient, as it leverages the browser's built-in formatting capabilities.
Cons:
	* May not work correctly if the input is not a number or if the desired precision is higher than 2 decimal places.
3. **`parseFloat(x.toFixed(2))`**: This approach first formats `x` as a string with 2 decimal places using `toFixed()` and then converts it back to a float using `parseFloat()`. The pros include:
	* Eliminates the need for the Lodash library.
Cons:
	* More computationally expensive than the other two approaches, as it involves an extra function call and conversion step.

**Special JavaScript Feature**

There is no special JavaScript feature or syntax mentioned in this benchmark. All three approaches rely on standard JavaScript methods and libraries.

**Other Alternatives**

If you want to explore alternative rounding strategies, consider:

1. **Using a decimal arithmetic library**: Libraries like Decimal.js provide precise decimal arithmetic, which can be useful for financial calculations.
2. **Implementing your own rounding algorithm**: If performance is critical, you could implement a custom rounding algorithm using bitwise operations or other low-level techniques.

Keep in mind that the choice of rounding approach depends on the specific requirements and constraints of your project.

Related benchmarks:

lodash.round VS toFixed() VS toFixed() and parseFloat (version: 0)

Compare round lodash function vs javascript native toFixed() function

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

Created: 6 years ago by: Guest

Jump to the latest result

Round floating number using lodash round function

Round floating number using toFixed()

Round floating number using toFixed() and parseFloat

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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