Benchmark: parseInt vs toFixed vs interpolated parseInt vs vs ~~

HTML Preparation code:

<div id="num"></div>

Script Preparation code:

var el = document.getElementById('num');
var arr = [];

Tests:

parseInt
var decimal = 30.0; for (var i = 0; i < 10000; i++) { decimal += (i / 1000); arr.push('parseInt ' + parseInt(decimal, 10)); }
toFixed
var decimal = 30.0; for (var i = 0; i < 10000; i++) { decimal += (i / 1000); arr.push('toFixed ' + decimal.toFixed()); }
~~
var decimal = 30.0; for (var i = 0; i < 10000; i++) { decimal += (i / 1000); arr.push('tilde ' + ~~decimal); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
parseInt
toFixed
~~

Fastest: N/A

Slowest: N/A

Latest run results:

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

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Let's break down the provided JSON and explain what's being tested in each test case.

**Overview**

The benchmark measures the performance of three different ways to parse numbers: `parseInt`, `toFixed`, and the tilde operator (`~~`). The goal is to determine which method is the fastest for a specific use case.

**Test Cases**

1. **`parseInt`**
	* The script preparation code creates an empty array `arr`.
	* In each iteration of the loop (10000 times), it appends a string to the array using `parseInt(decimal, 10)`, where `decimal` is initially set to 30.0.
	* This method parses a decimal number and converts it to an integer, which may involve rounding errors if the decimal part has no fractional digits.
2. **`toFixed`**
	* Similar to `parseInt`, but instead of parsing a decimal number, it uses `decimal.toFixed()` to format `decimal` as a fixed-point number with two decimal places (i.e., `30.00`).
3. **`~~` (Tilde Operator)**
	* This method is equivalent to rounding down the nearest integer using the modulo operator (`decimal % 1`) or by performing integer division and then subtracting the result from the original value.
	* In this case, it uses the tilde operator (`~~`) to round `decimal` down.

**Options Compared**

The benchmark compares the performance of these three methods:

* **Parsing vs Rounding**: Each method has its own approach to handling decimal numbers. `parseInt` may introduce rounding errors if the input is not an integer, while `toFixed` provides a fixed-point representation with two decimal places. The tilde operator (`~~`) rounds down the nearest integer.
* **Performance**: The benchmark measures which method executes faster.

**Pros and Cons**

* **`parseInt`**:
	+ Pros: Simple to implement and widely supported in JavaScript engines.
	+ Cons: May introduce rounding errors if input is not an integer, can be slow for large numbers or decimal values with multiple fractional digits.
* **`toFixed`**:
	+ Pros: Provides a fixed-point representation, which might be useful in certain applications (e.g., financial calculations).
	+ Cons: Can be slower than the tilde operator due to string formatting overhead.
* **Tilde Operator (`~~`)**
	+ Pros: Fast and efficient for integer arithmetic, rounds down to nearest integer.
	+ Cons: May not provide a meaningful result if the input is not an integer.

**Library/Dependency**

None of the test cases explicitly use any external libraries or dependencies. However, `toFixed` relies on the String.prototype.toFixed method, which might be implemented using browser-specific features like WebAssembly (if available).

**Special JS Feature/Syntax**

The tilde operator (`~~`) is a built-in JavaScript feature that rounds down to the nearest integer.

**Alternatives**

If you want to benchmark other approaches or alternatives, consider:

* **`Number()` vs `parseInt()`**: Compare the performance of parsing decimal numbers using `Number()` (which can be slower due to type checking) versus `parseInt()`.
* **`toFixed()` with different precision**: Measure how performance changes when using a higher or lower precision for fixed-point formatting.
* **Other rounding methods**: Explore alternative rounding methods, such as `Math.round()` or custom implementations, to see if they outperform the tilde operator (`~~`) in your specific use case.

Related benchmarks:

parseInt vs toFixed vs interpolated parseInt vs vs ~~ (version: 0)

Comparing performance of: parseInt vs toFixed vs ~~

Created: 4 years ago by: Guest

Jump to the latest result

parseInt

toFixed

~~

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):