Benchmark: parseInt vs Number parsing

Script Preparation code:

var strB = "42.034";

Tests:

No conversion
var res = +strB;
parseInt
var res = parseInt(strB);
Number
var res = Number(strB);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
No conversion
parseInt
Number

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36

Browser/OS: Chrome 133 on Windows

View result in a separate tab

Test name	Executions per second
No conversion	211762624.0 Ops/sec
parseInt	214538688.0 Ops/sec
Number	203509312.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into explaining the benchmark.

**Benchmark Overview**

The provided JSON represents a JavaScript microbenchmark test case on MeasureThat.net. The purpose of this benchmark is to compare the performance of three different ways to parse a string representing a floating-point number: `parseInt`, `Number`, and explicit conversion using the unary plus operator (`+`).

**Options Being Compared**

The benchmark tests three options:

1. **No Conversion**: This option uses the implicit conversion of a string to a number using the unary plus operator (`+`). The `+` operator attempts to parse the string as an integer if possible, and falls back to parsing it as a floating-point number.
2. **parseInt**: This option uses the built-in `parseInt()` function from JavaScript's standard library to parse the string as an integer.
3. **Number**: This option uses the built-in `Number()` function from JavaScript's standard library to parse the string as a floating-point number.

**Pros and Cons of Each Approach**

1. **No Conversion**:
	* Pros: Does not require loading any additional libraries, which can reduce overhead.
	* Cons: May be slower due to the implicit conversion process, which involves checking if the string is an integer and then parsing it as a float if necessary.
2. **parseInt**:
	* Pros: Efficiently parses integers by skipping the check for floating-point values, making it faster than the no-conversion approach.
	* Cons: Will throw a `NaN` (Not a Number) result if the string is not an integer, requiring additional error handling.
3. **Number**:
	* Pros: Provides a more straightforward and safer way to parse strings as floats compared to the explicit conversion with `+`.
	* Cons: May be slower than `parseInt` due to the overhead of parsing the entire string as a float.

**Library Usage**

None of these options use any external libraries, making it easy to run this benchmark in various environments.

**Special JavaScript Feature/Syntax**

The unary plus operator (`+`) is used implicitly to convert the string to a number. This syntax is specific to JavaScript and allows for implicit conversion between strings and numbers.

**Other Alternatives**

If you want to explore more options or alternatives, here are a few:

* Using `Number()` with a radix argument (e.g., `Number(strB, 10)`) to parse the string as an integer with a specific radix.
* Implementing custom parsing logic using regular expressions or other approaches.

Keep in mind that these alternative approaches might have varying degrees of overhead, and may not always outperform the original options.

Related benchmarks:

parseInt vs Number parsing (version: 0)

Comparing performance of: No conversion vs parseInt vs Number

Created: 4 years ago by: Guest

Jump to the latest result

No conversion

parseInt

Number

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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