Benchmark: perf check - MeasureThat.net

Script Preparation code:

var nested = Array.from({
    length: 10000
}).map(() => Math.floor(Math.random() * Math.floor(10)));
var list = [2,3,4,5];

Tests:

1
nested.map(item => { if (list.indexOf(item) === -1) { list.push(item); } });
2
const selectedNested = nested.filter(item => list.indexOf(item) === -1); list = list.concat(selectedNested);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
1
2

Fastest: N/A

Slowest: N/A

Latest run results:

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

The provided JSON represents a benchmark test case, which consists of two individual tests (or "test cases") that compare different approaches to achieve a specific goal. In this case, both tests aim to find elements in an array (`list`) and add them to another array (`nested`), if they are not already present.

**Benchmark Definition**

The benchmark definition is a JSON object that contains two scripts:

1. **Script Preparation Code**: This code initializes the `nested` array with 10,000 random integers between 0 and 9, inclusive. It then creates an initial list `[2, 3, 4, 5]`.
2. **Html Preparation Code**: This field is empty, indicating that no HTML-related setup is required for this benchmark.

**Individual Test Cases**

The two test cases are defined as arrays of objects, each containing a `Benchmark Definition` and a `Test Name`. These definitions specify how to measure the performance of different approaches:

1. **Test 1**: The first test case uses the `map()` method to iterate over the `nested` array and add elements from the `list` that are not already present in `nested`.
```javascript
nested.map(item => {
  if (list.indexOf(item) === -1) {
    list.push(item);
  }
});
```
2. **Test 2**: The second test case uses the `filter()` method to remove elements from the `nested` array that are not present in the `list`, and then concatenates the filtered results with the `list`.
```javascript
const selectedNested = nested.filter(item => list.indexOf(item) === -1);
list = list.concat(selectedNested);
```
**Library Usage**

In both test cases, a library is used:

* In Test 1, `map()` is a native JavaScript method.
* In Test 2, `filter()` and `concat()` are also native JavaScript methods.

No external libraries are required to run these tests.

**Special JS Features/Syntax**

None of the provided code snippets utilize special JavaScript features or syntax. They are straightforward examples that demonstrate the use of basic array methods.

**Pros and Cons**

Here's a brief analysis of each approach:

1. **Test 1 (map())**:
	* Pros: Simple and efficient, uses native `map()` method.
	* Cons: Creates an intermediate array (`list`) that needs to be sorted in place, which can be expensive for large inputs.
2. **Test 2 (filter() + concat())**:
	* Pros: Avoids creating unnecessary intermediate arrays, as the filtered results are concatenated directly with the `list`.
	* Cons: Requires two separate operations (`filter()` and `concat()`), which might introduce additional overhead.

**Other Alternatives**

If you're interested in exploring alternative approaches, here are a few suggestions:

* Use a different data structure, such as a Set or a Map, to store the elements in the `list` instead of an array.
* Utilize a more efficient sorting algorithm, like QuickSort or Merge Sort, for large inputs.
* Consider using a library that provides optimized array operations, such as Lodash or Ramda.

Keep in mind that these alternatives might introduce additional complexity and may not always provide better performance. The best approach will depend on the specific use case and requirements of your project.

Related benchmarks:

perf check (version: 0)

Comparing performance of: 1 vs 2

Created: 5 years ago by: Guest

Jump to the latest result

1

2

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):