Benchmark: Join vs Map - MeasureThat.net

Tests:

Join
const a = [1, 2, 3, 4, 5, 6, 7, 8, 9] a.join('');
Map
const a = [1, 2, 3, 4, 5, 6, 7, 8, 9] a.map(String)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Join
Map

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested.

**Benchmark Definition**

The benchmark definition is empty, which means that the script preparation code and HTML preparation code are not provided. This is likely because the specific scripts and setup are already included in the individual test cases.

**Individual Test Cases**

There are two test cases:

1. **Join**: This test case measures the performance of the `join()` method on an array.
```javascript
const a = [1, 2, 3, 4, 5, 6, 7, 8, 9];
a.join('');
```
The purpose of this test is to measure how fast the browser can concatenate the elements in the array using the `join()` method.

2. **Map**: This test case measures the performance of the `map()` method with a callback function that converts each element to a string.
```javascript
const a = [1, 2, 3, 4, 5, 6, 7, 8, 9];
a.map(String);
```
The purpose of this test is to measure how fast the browser can apply the `String` function to each element in the array using the `map()` method.

**Options Compared**

In both cases, the same operation (concatenating or mapping) is being performed on the same array. The difference lies in the approach:

* **Join**: The `join()` method concatenates all elements in the array into a single string.
* **Map**: The `map()` method applies a function to each element in the array and returns a new array with the results.

**Pros and Cons**

**Join**

Pros:

* Faster execution time, as it only requires a single operation to concatenate all elements.
* Less memory usage, as no intermediate arrays are created.

Cons:

* May not be suitable for operations that require multiple iterations or filtering.

**Map**

Pros:

* More flexible, as the callback function can perform complex operations on each element.
* Easier to read and maintain code, as it separates the data processing from the result concatenation.

Cons:

* Generally slower execution time due to the need to create an intermediate array and apply the function to each element.
* Higher memory usage, as an intermediate array is created to store the results.

**Other Considerations**

* Both tests assume that the input array has a specific size (9 elements) and does not handle edge cases like empty arrays or arrays with non-numeric values.
* The `String` function used in the `Map` test case is likely intended to convert each element to a string, but this can be adjusted depending on the specific use case.

**Library**

There is no explicit library mentioned in the benchmark definition. However, some browsers may have additional libraries or extensions that could affect the performance of these tests (e.g., Safari's WebKit engine).

**Special JS Feature/Syntax**

None are explicitly used in this benchmark.

**Alternatives**

Other alternatives to `join()` and `map()` include:

* **Reduce()**: A method similar to `join()`, but it requires a callback function to specify the aggregation operation.
* **forEach()**: A method that allows iterating over an array without creating an intermediate array, but it does not provide any benefits for this specific use case.

For mapping operations, alternative approaches include:

* Using `filter()` followed by `map()` or other array methods to process the data.
* Utilizing libraries like Lodash or Ramda, which provide more functional programming features and optimized performance.

Keep in mind that these alternatives may have different performance characteristics and are often used for specific use cases.

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.1 Safari/605.1.15

Browser/OS: Safari 14 on Mac OS X 10.15.6

View result in a separate tab

Test name	Executions per second
Join	7902403.5 Ops/sec
Map	3970513.2 Ops/sec

Related benchmarks:

Join vs Map (version: 0)

Comparing performance of: Join vs Map

Created: 3 years ago by: Guest

Jump to the latest result

Join

Map

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):