Benchmark: Find last element of an array no empty array

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var arr1 = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
var arr2 = [];

function lodashFindLast(arr, n) {
  const element = _.findLast(arr);
  return element === n;
}

function lengthLast(arr, n) {
  const element = arr[arr.lenght - 1];
  return element === n;
}

function popLast(arr, n) {
  const element = arr.pop();
  return element === n;
}

function sliceArray(arr, n) {
  const element = arr.slice(-1);
  return element === n;
}

Tests:

lodash
lodashFindLast(arr1, 8); lodashFindLast(arr1, 9);
length-1
lengthLast(arr1, 8); lengthLast(arr1, 9);
slice
sliceArray(arr1, 8); sliceArray(arr1, 9);
pop
popLast(arr1, 8); popLast(arr1, 9);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash
length-1
slice
pop

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and test cases.

**Benchmark Definition:**

The benchmark measures the performance of four different approaches to find the last element in an array:

1. `lodashFindLast(arr, n)`: Uses the Lodash library to find the last element that matches a given value.
2. `lengthLast(arr, n)`: Manually accesses the last element of the array by calculating its index (`arr.length - 1`) and comparing it with the target value.
3. `popLast(arr, n)`: Removes the last element from the array using `arr.pop()` and checks if the removed element matches the target value.
4. `sliceArray(arr, n)`: Slices the array to get only the last element using `arr.slice(-1)` and compares it with the target value.

**Options Compared:**

The benchmark compares the performance of these four approaches:

* **Lodash**: Uses the `lodash.findLast` function to find the last element that matches a given value.
	+ Pros: Efficient and concise way to find the last matching element in an array.
	+ Cons: Requires including the Lodash library, which may add overhead.
* **Manual Indexing**: Manually accesses the last element of the array by calculating its index (`arr.length - 1`) and comparing it with the target value.
	+ Pros: Simple and lightweight approach that doesn't require any libraries.
	+ Cons: May be slower than other approaches due to manual calculations.
* **Array Pop**: Removes the last element from the array using `arr.pop()` and checks if the removed element matches the target value.
	+ Pros: Efficiently removes the last element and can be faster than manual indexing.
	+ Cons: Modifies the original array, which may not be desirable in some cases.
* **Array Slicing**: Slices the array to get only the last element using `arr.slice(-1)` and compares it with the target value.
	+ Pros: Efficiently gets the last element without modifying the original array.
	+ Cons: May be slower than other approaches due to slicing.

**Library:**

The benchmark uses the Lodash library (version 4.17.5) for its `lodashFindLast` function, which provides a convenient and efficient way to find the last matching element in an array.

**Special JS Feature/Syntax:**

There are no special JavaScript features or syntax used in these test cases. The focus is on comparing different approaches to find the last element in an array.

**Other Alternatives:**

Other alternatives that could be considered for finding the last element in an array include:

* Using a `for` loop to iterate through the array and check each element manually.
* Using a more advanced library like jQuery or a custom solution using a different data structure (e.g., a stack).

However, these alternatives are not included in this benchmark definition.

**Benchmark Preparation Code:**

The provided JavaScript code defines four functions:

* `lodashFindLast(arr, n)`: Uses Lodash to find the last matching element.
* `lengthLast(arr, n)`: Manually accesses the last element of the array.
* `popLast(arr, n)`: Removes the last element and checks if it matches the target value.
* `sliceArray(arr, n)`: Slices the array to get only the last element.

The code also includes a brief description for each function.

**HTML Preparation Code:**

The provided HTML code includes a script tag that loads the Lodash library (version 4.17.5) from a CDN, making it available for use in the benchmark tests.

Latest run results:

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

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/117.0

Browser/OS: Firefox 117 on Ubuntu

View result in a separate tab

Test name	Executions per second
lodash	3139824.5 Ops/sec
length-1	4571290.0 Ops/sec
slice	7946325.0 Ops/sec
pop	70403416.0 Ops/sec

Related benchmarks:

Find last element of an array no empty array (version: 0)

Find last element of an array no empty array

Comparing performance of: lodash vs length-1 vs slice vs pop

Created: one year ago by: Registered User

Jump to the latest result

lodash

length-1

slice

pop

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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