Benchmark: trunc-benchmark - MeasureThat.net

Script Preparation code:

function dosDecimales(n) {
  let t=n.toString();
  let regex=/(\d*.\d{0,2})/;
  return t.match(regex)[0];
}

function trunc (x, posiciones = 0) {
  var s = x.toString()
  var l = s.length
  var decimalLength = s.indexOf('.') + 1

  if (l - decimalLength <= posiciones){
    return x
  }
  // Parte decimal del número
  var isNeg  = x < 0
  var decimal =  x % 1
  var entera  = isNeg ? Math.ceil(x) : Math.floor(x)
  // Parte decimal como número entero
  // Ejemplo: parte decimal = 0.77
  // decimalFormated = 0.77 * (10^posiciones)
  // si posiciones es 2 ==> 0.77 * 100
  // si posiciones es 3 ==> 0.77 * 1000
  var decimalFormated = Math.floor(
    Math.abs(decimal) * Math.pow(10, posiciones)
  )
  // Sustraemos del número original la parte decimal
  // y le sumamos la parte decimal que hemos formateado
  var finalNum = entera + 
    ((decimalFormated / Math.pow(10, posiciones))*(isNeg ? -1 : 1))
  
  return finalNum
}

function trunc2 (x, posiciones = 0) {
  var s = x.toString()
  var l = s.length
  var decimalLength = s.indexOf('.') + 1
  var numStr = s.substr(0, decimalLength + posiciones)
  return Number(numStr)
}

Tests:

Trunc Mat
trunc(17.97777, 2)
Trunc
trunc2(17.97777, 2)
dosDecimales
dosDecimales(17.97777, 2)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Trunc Mat
Trunc
dosDecimales

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:135.0) Gecko/20100101 Firefox/135.0

Browser/OS: Firefox 135 on Windows

View result in a separate tab

Test name	Executions per second
Trunc Mat	11120801.0 Ops/sec
Trunc	8852710.0 Ops/sec
dosDecimales	12720116.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested.

**Benchmark Definition**

The benchmark is testing three different approaches to truncate (round down) decimal numbers in JavaScript:

1. `trunc(x, posiciones = 0)` - This function takes two arguments: a number `x` and an optional position `posiciones`. It returns the truncated value of `x` with the specified number of positions after the decimal point.
2. `trunc2(x, posiciones = 0)` - Similar to `trunc`, but it uses string manipulation to extract the desired part of the number.
3. `dosDecimales(n, posiciones = 0)` - This function takes two arguments: a number `n` and an optional position `posiciones`. It returns the truncated value of `n` with the specified number of positions after the decimal point.

**Options Compared**

The three functions are being compared in terms of performance (executions per second). The results will show which approach is faster for each test case.

**Pros and Cons of Each Approach**

1. `trunc(x, posiciones = 0)`:
	* Pros: Easy to understand and implement, uses built-in JavaScript functionality.
	* Cons: May be slower due to the overhead of creating a new number object.
2. `trunc2(x, posiciones = 0)`:
	* Pros: Can be faster since it avoids the overhead of creating a new number object.
	* Cons: Requires string manipulation, which can be slower than numeric operations.
3. `dosDecimales(n, posiciones = 0)`:
	* Pros: Uses a custom implementation that might be optimized for specific use cases.
	* Cons: May not be as widely supported or understood as the other two approaches.

**Library and Syntax**

None of the functions in this benchmark rely on any external libraries. The syntax is standard JavaScript, with no special features or syntax.

**Considerations**

When implementing these functions, consider the trade-offs between performance, readability, and maintainability. For example:

* When using `trunc(x, posiciones = 0)`, ensure that the built-in number object is properly initialized to avoid issues.
* When using `dosDecimales(n, posiciones = 0)`, test thoroughly to ensure that the custom implementation works correctly for all edge cases.

**Alternatives**

If you need to perform similar tasks in your code, consider these alternatives:

1. Use built-in functions like `Math.trunc()` (available in modern browsers and Node.js) or `Number.EPSILON` (a small value used by JavaScript to represent floating-point errors).
2. Implement a custom implementation using bitwise operations, but be aware that this can be error-prone and may not work correctly for all use cases.
3. Use libraries like [Big.js](https://github.com/mike-leclerc/Big.js) or [Decimal.js](https://m1sh4n.github.io/decimal-js/) to perform decimal arithmetic, but be aware that these libraries may have additional dependencies and complexity.

In summary, the `trunc(x, posiciones = 0)` function uses built-in JavaScript functionality, while `trunc2(x, posiciones = 0)` relies on string manipulation. The custom implementation in `dosDecimales(n, posiciones = 0)` might be optimized for specific use cases but requires thorough testing.

Related benchmarks:

trunc-benchmark (version: 0)

trunc

Comparing performance of: Trunc Mat vs Trunc vs dosDecimales

Created: 7 years ago by: Guest

Jump to the latest result

Trunc Mat

Trunc

dosDecimales

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):