Benchmark: Array.from vs map

Tests:

Array.from
Array.from({ length: 10 }, i => i)
Map
new Array(10).map(i => i);
Loop
const arr = new Array(10); for (let i = 0; i < 10; i++) arr[i] = i
Loop push
const arr = [] for (let i = 0; i < 10; i++) arr.push(i)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.from
Map
Loop
Loop push

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 days ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.1 Safari/605.1.15

Browser/OS: Safari 18 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array.from	21848822.0 Ops/sec
Map	5443367.0 Ops/sec
Loop	52351472.0 Ops/sec
Loop push	45292820.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what is being tested, compared options, pros and cons, and other considerations.

**Benchmarked Feature:**

The main feature being measured in this benchmark is array creation in JavaScript using different methods:

* `Array.from()`
* `map()` method
* Manual loops (using `for` loop or `push()` method)

**Comparison of Options:**

The benchmark compares the performance of three array creation methods:

1. **`Array.from()`**: Creates an array from a specified length and iterable. In this case, it's used to create an array of numbers from 0 to 9.
2. **`map()` method**: Applies a callback function to each element of an existing array, returning a new array with the results.
3. **Manual Loops**:
	* `for` loop: Uses a traditional `for` loop to iterate over the numbers and assign them to an array.
	* `push()` method: Creates an empty array and pushes each number into it using the `push()` method.

**Pros and Cons of Each Approach:**

1. **`Array.from()`**:
	* Pros: Efficient, concise, and easy to read.
	* Cons: May incur additional overhead due to the creation of an intermediate iterable object.
2. **`map()` method**:
	* Pros: Flexible, as it can be used with existing arrays or iterables.
	* Cons: Can be slower than `Array.from()` for simple array creations.
3. **Manual Loops**:
	* Pros: Provides control over the creation process and can be optimized for specific use cases.
	* Cons: More verbose and less efficient compared to `Array.from()` and `map()`.

**Other Considerations:**

* The benchmark uses Chrome 129 as the test browser, which may not be representative of all browsers.
* The device platform is set to Desktop, which may affect the results due to differences in rendering and performance.
* The operating system is Windows, which may also influence the results.
* The `executionsPerSecond` metric measures the number of iterations performed per second, providing an indication of performance.

**Library Usage:**

None of the benchmarked methods explicitly use a JavaScript library. However, it's worth noting that some libraries like Lodash or Ramda might provide similar functions (e.g., `map()`) with their own optimizations.

**Special JS Features/Syntax:**

This benchmark does not explicitly test any special JavaScript features or syntax. The focus is on comparing the performance of different array creation methods.

**Alternatives:**

Other alternatives for array creation in JavaScript include:

* Using `Array.prototype.fill()` to create an array filled with a specific value.
* Utilizing WebAssembly (WASM) modules to perform efficient array operations.
* Leveraging specialized libraries like NumJS or jsArray, which are designed for numerical computations and provide optimized array implementations.

Keep in mind that the choice of array creation method depends on the specific use case and performance requirements.

Related benchmarks:

Array.from vs map (version: 0)

Comparing performance of: Array.from vs Map vs Loop vs Loop push

Created: 4 years ago by: Guest

Jump to the latest result

Array.from

Map

Loop

Loop push

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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