Benchmark: map vs for loop (for arrays includes 35k)

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/react/16.3.0/cjs/react.production.min.js'></script>

Script Preparation code:

var a = [];
for (var i = 0; i < 35000; i++) {
  a[i] = {id: Math.random(), name: 'no_name' + 1, price: Math.floor(Math.random() * 50000) + 1 };
}

Tests:

map
var b = []; a.map(n => b.push(n)); return b;
for loop
var b = []; for (var i = 0; i < a.length; i++) { } return b;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
map
for loop

Fastest: N/A

Slowest: N/A

Latest run results:

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

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Let's break down the provided JSON data for MeasureThat.net, a website that enables users to create and run JavaScript microbenchmarks.

**Benchmark Definition:**

The benchmark is designed to compare two methods for checking if an element exists in an array:

1. `map()` method
2. For loop iteration (`for` statement)

**Script Preparation Code:**

The script prepares an array `a` with 35,000 elements, each containing a random `id`, `name`, and `price`. This is done to ensure that both test cases have access to a large dataset.

```javascript
var a = [];
for (var i = 0; i < 35000; i++) {
    a[i] = { id: Math.random(), name: 'no_name' + 1, price: Math.floor(Math.random() * 50000) + 1 };
}
```

**Html Preparation Code:**

The HTML code includes a reference to React version 16.3.0, which is likely included for testing purposes.

```javascript
<script src='https://cdnjs.cloudflare.com/ajax/libs/react/16.3.0/cjs/react.production.min.js'></script>
```

**Individual Test Cases:**

There are two test cases:

1. **`map()` method:**
   ```javascript
var b = [];
a.map(n => b.push(n));
return b;
```
   This test case uses the `map()` function to iterate over the array `a`, pushing each element into a new array `b`. However, since `push()` also modifies the original array's length, this approach is not ideal for checking if an element exists in the array.

2. **For loop iteration (`for` statement):**
   ```javascript
var b = [];
for (var i = 0; i < a.length; i++) {
}
return b;
```
   This test case uses a traditional `for` loop to iterate over the array `a`, but does not actually access or push any elements into the array `b`. It only iterates over the indices of the array without modifying them.

**Pros and Cons:**

- **`map()` method:** 
  - Pros:
    * Efficient for creating a new array with transformed data.
    - Can be used to check if an element exists in the original array using `includes()`.
  - Cons:
    * Modifies the original array's length, which can impact performance tests.
    * May not be suitable for checking exact matches or unique elements.

- **For loop iteration (`for` statement):**
  - Pros:
    * Does not modify the original array's length.
    * Can provide more control over the iteration process.
  - Cons:
    * Less efficient than using `map()` for creating new arrays.
    * Typically used with indexing and may require manual checks for existence.

**Library and Special JS Features:**

- **React:** 
  React is a JavaScript library for building user interfaces. In this benchmark, it's likely included to test the performance of the JavaScript engine in a web context. However, its presence doesn't directly impact the comparison between `map()` and traditional loop iteration.

**Other Considerations:**

When choosing between these approaches, consider the specific requirements of your application:

- If you need to create a new array with transformed data or check if an element exists in the original array using `includes()`, the `map()` method might be more suitable.
- If you require manual control over the iteration process or need to access elements without modifying the original array's length, the traditional loop iteration (`for` statement) might be a better choice.

**Alternative Approaches:**

Other alternatives for checking if an element exists in an array include:

- Using `includes()`, which is often the most efficient way to check for existence.
- Utilizing other methods like `forEach()` or `every()` with callback functions, depending on your specific requirements.

Related benchmarks:

map vs for loop (for arrays includes 35k) (version: 0)

compare methods for array includes 35k items

Comparing performance of: map vs for loop

Created: 2 years ago by: Guest

Jump to the latest result

map

for loop

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):