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)
}

function trunc_fixed (x, posiciones = 0) {
  return +x.toFixed(posiciones);
}

var pows = new Array(32).fill().map(function(_ ,i) {return Math.pow(10,i);});

function trunc_pows (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) * pows[posiciones]
  )
  // Sustraemos del número original la parte decimal
  // y le sumamos la parte decimal que hemos formateado
  var finalNum = entera + 
    ((decimalFormated / pows[posiciones])*(isNeg ? -1 : 1))
  
  return finalNum
}

function quick_pows (x, posiciones = 0) {
  return (x*pows[posiciones] | 0) / pows[posiciones];
}

console.log(pows);
console.log(trunc_pows(17.2345, 2));

Tests:

Trunc Mat
trunc(17.97777, 2)
Trunc
trunc2(17.97777, 2)
dosDecimales
dosDecimales(17.97777, 2)
trunc_fixed
trunc_fixed(17.97777, 2)
trunc_pows
trunc_pows(17.97777, 2)
quick_pows
quick_pows(17.97777, 2)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Trunc Mat
Trunc
dosDecimales
trunc_fixed
trunc_pows
quick_pows

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's dive into the benchmark.

**Benchmark Overview**

The benchmark measures the performance of different JavaScript functions that truncate decimal numbers to a specified number of positions. The benchmarks are written in a specific order, which might affect their relative performance.

**Functions Being Tested**

1. `dosDecimales(n)`: This function takes an integer `n` as input and returns its string representation with only two decimal places.
2. `trunc(x, posiciones = 0)`: This function truncates the decimal part of a number `x` to `posiciones` positions. The default value of `posiciones` is 0, which means no decimal part is truncated.
3. `trunc2(x, posiciones = 0)`: Similar to `trunc`, but it's not clear why this function exists since `dosDecimales` already achieves the same result.
4. `trunc_fixed(x, posiciones = 0)`: This function truncates the decimal part of a number `x` to `posiciones` positions and returns an integer value.
5. `trunc_pows(x, posiciones = 0)`: This function uses a mathematical approach to truncate the decimal part of a number `x` to `posiciones` positions.
6. `quick_pows(x, posiciones = 0)`: This function also truncates the decimal part of a number `x` to `posiciones` positions but uses a different algorithm.

**Observations**

* The `trunc2` function is not as efficient as the other functions that achieve similar results.
* The `trunc_pows` and `quick_pows` functions are almost identical, with only minor differences in their implementation details.
* The `dosDecimales` function seems to be a slowest among all functions.

**Conclusion**

The benchmark provides valuable insights into the performance of different JavaScript functions for truncating decimal numbers. Based on the results:

1. Use `trunc_pows` or `quick_pows` for optimal performance, as they are very similar and likely have negligible differences.
2. Avoid using `dosDecimales`, as it is significantly slower than the other options.
3. The existence of `trunc2` suggests that the developer was experimenting with different approaches, but it's not clear why this function wasn't refactored or optimized further.

I hope this analysis helps you understand the benchmark results!

Related benchmarks:

trunc-benchmark (version: 0)

trunc

Comparing performance of: Trunc Mat vs Trunc vs dosDecimales vs trunc_fixed vs trunc_pows vs quick_pows

Created: 8 years ago by: Guest

Jump to the latest result

Trunc Mat

Trunc

dosDecimales

trunc_fixed

trunc_pows

quick_pows

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):