Benchmark: Float string optimization: parseFloat() vs regex for getFirstNumber2

Tests:

regex
function getFirstNumberUsingRegex(...numbers) { let result; numbers.forEach((num) => { const isNumber = /^-?\d*\.?\d*$/.test(String(num)); if (!result && isNumber) { result = Number(num); } }); return result; } const result1 = getFirstNumberUsingRegex(-10, '10', 100, '$'); console.log(result1);
parsefloat
function getFirstNumberUsingParseFloat(...numbers) { let result; numbers.forEach((num) => { const isNumber = parseFloat(num); if (!result && isNumber) { result = Number(num); } }); return result; } const result2 = getFirstNumberUsingParseFloat(-10, '10', 100, '$'); console.log(result2);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
regex
parsefloat

Fastest: N/A

Slowest: N/A

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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.

**Benchmark Definition**

The benchmark definition describes two approaches to extract the first number from an array of strings:

1. `getFirstNumberUsingRegex`: This function uses regular expressions (regex) to test if a string is a valid number. If it finds the first valid number, it returns its numeric value.
2. `getFirstNumberUsingParseFloat`: This function uses the built-in `parseFloat` function to attempt to convert each string in the array to a float. If it finds the first valid number, it returns its numeric value.

**Options Compared**

The benchmark compares the performance of these two approaches:

* Regex approach (`getFirstNumberUsingRegex`)
* `parseFloat` approach (`getFirstNumberUsingParseFloat`)

**Pros and Cons of Each Approach**

**Regex Approach**

Pros:

* More flexible and powerful for parsing numbers with optional decimal points, sign, and radix.
* Can be more efficient if only the first valid number needs to be extracted.

Cons:

* May have slower performance due to the complexity of regex patterns.
* Requires more code and maintenance effort compared to `parseFloat`.

**parseFloat Approach**

Pros:

* Faster execution since it's a built-in function optimized for performance.
* Less code and easier maintenance.

Cons:

* May not work correctly if the input string is malformed or doesn't contain any valid numbers.
* Can be less flexible than regex in terms of parsing numbers with optional decimal points, sign, and radix.

**Library/Function**

Both approaches use a library or function to test their performance. `parseFloat` is a built-in JavaScript function, while no specific regex pattern is provided; however, the implementation assumes a simple regex pattern (`^ -?\d* \.?$`) is used implicitly.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntaxes being tested in this benchmark. The code uses standard JavaScript syntax and built-in functions.

**Alternative Approaches**

Other alternatives for extracting the first number from an array of strings could include:

1. Using a dedicated library like `lodash` with its `first` function.
2. Implementing a custom parser using regular expressions or a parsing algorithm (e.g., Lex-Yacc).
3. Utilizing other built-in functions like `String.prototype.match` or `String.prototype.replace`.

However, the regex approach and `parseFloat` approach are likely the most common and efficient methods for this specific use case.

**Benchmark Preparation Code**

The provided benchmark preparation code includes two JavaScript functions (`getFirstNumberUsingRegex` and `getFirstNumberUsingParseFloat`) that implement the respective approaches. The code also defines a test setup, which creates an array of strings to be processed by each function.

I hope this explanation helps!

Related benchmarks:

Float string optimization: parseFloat() vs regex for getFirstNumber2 (version: 0)

Comparing performance of: regex vs parsefloat

Created: 4 years ago by: Registered User

Jump to the latest result

regex

parsefloat

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):