Benchmark: Array_diff - MeasureThat.net

Script Preparation code:

var a = [1,2,2,2,3,4,5,6,8,4,5,8,4,6,3,5];
var b = [2,4];

Tests:

Best
function array_diff(a, b) { return a.filter(function(x) { return b.indexOf(x) == -1; }); }
Mine
function array_diff(a, b) { let arrStr = a.join(''); b.forEach(function(item) { arrStr = arrStr.replace(new RegExp(item, 'g'), ''); }); return arrStr.split('').map(function(t){return parseInt(t)}); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Best
Mine

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36

Browser/OS: Chrome 123 on Windows

View result in a separate tab

Test name	Executions per second
Best	149050448.0 Ops/sec
Mine	146135952.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Explanation**

The provided JSON represents two JavaScript microbenchmarks, `Array_diff`, which tests the performance of different approaches to find the elements in array `a` that are not present in array `b`. The benchmarks are designed to measure the execution speed and efficiency of these approaches.

**Approaches Compared**

There are two approaches being compared:

1. **Filter Method**: The first approach uses the `filter()` method, which creates a new array with all elements that pass a test implemented by a provided function. In this case, the filter function checks if each element in `a` is not present in `b` using the `indexOf()` method.
2. **Replace and Split Methods**: The second approach uses a more complex algorithm involving string manipulation:
	* It joins all elements of `a` into a single string `arrStr`.
	* It iterates over `b` and replaces each element with an empty string in `arrStr` using a regular expression.
	* Finally, it splits the modified `arrStr` into an array of integers using `split()`.

**Pros and Cons**

1. **Filter Method**
	* Pros: Simple to implement, efficient, and easy to understand.
	* Cons: May not be suitable for large datasets due to the overhead of creating a new array.
2. **Replace and Split Methods**
	* Pros: Can handle large datasets efficiently by manipulating strings instead of arrays.
	* Cons: More complex implementation, may involve unnecessary string operations.

**Library Usage**

There is no explicit library usage mentioned in the provided code snippets.

**Special JS Features or Syntax**

No special JavaScript features or syntax are used beyond what is standard for modern JavaScript programming. The focus is on comparing different algorithmic approaches to achieve a specific goal.

**Alternative Approaches**

Other possible approaches to solve this problem could include:

* Using `Set` data structure: Convert one of the arrays to a set, which automatically removes duplicates, and then filter out elements from the other array using `has()` method.
* Using `Map` data structure: Similar to the Set approach, but with the advantage of preserving element order.

However, these alternatives are not explicitly represented in the provided benchmark code snippets.

Related benchmarks:

Array_diff (version: 0)

Comparing performance of: Best vs Mine

Created: 9 years ago by: Guest

Jump to the latest result

Best

Mine

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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