Benchmark: Map vs For Loop 2

Tests:

Map
var a = []; for (var i = 0; i < 1e6; i++) { a[i] = Math.random(); } var b = a.map(n => n * 2); console.log('map', b[0]);
For Loop
var a = []; for (var i = 0; i < 1e6; i++) { a[i] = Math.random(); } var b = []; for (var i = 0; i < a.length; i++) { b[i] = a[i] * 2; } console.log('for', b[0]);

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:

Run details: (Test run date: 7 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36

Browser/OS: Chrome 55 on Windows

View result in a separate tab

Test name	Executions per second
Map	1.9 Ops/sec
For Loop	4.1 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 benchmark and explain what's being tested, compared, and discussed.

**Benchmark Overview**

The benchmark compares the performance of two approaches to multiply an array by 2: using `Array.prototype.map()` (the "Map" test case) versus a traditional for loop (the "For Loop" test case).

**What is being compared?**

* **Performance**: The benchmark measures how many elements in the resulting array are processed per second. This indicates the overall efficiency of each approach.

**Options compared:**

1. **Map**: Uses `Array.prototype.map()` to create a new array with transformed elements.
2. **For Loop**: Iterates over the original array using a traditional for loop, multiplying each element by 2 and storing the result in a new array.

**Pros and Cons of each approach:**

* **Map**:
	+ Pros:
		- Cleaner and more concise code.
		- Easier to read and maintain.
	+ Cons:
		- May incur overhead due to function call and creation of a new array.
		- Less control over the iteration process.
* **For Loop**:
	+ Pros:
		- More control over the iteration process.
		- Can be optimized for specific use cases.
	+ Cons:
		- Longer, more verbose code.

**Library used:**

None. Both test cases rely on built-in JavaScript features.

**Special JS feature or syntax:**

* **Array.prototype.map()**: Introduced in ECMAScript 2015 (ES6), this method allows for concise array transformations.
* **For loop with `var i = 0; i < a.length; i++`**: A common pattern used to iterate over arrays.

**Other considerations:**

* The benchmark uses a large array size (`1e6`) to emphasize performance differences.
* Both test cases use the same starting value and multiplication factor, ensuring that any observed performance difference is due to the iteration approach rather than other factors.

**Alternatives:**

If you were to implement this benchmark yourself or optimize it, some alternatives could be explored:

* Using `Array.prototype.forEach()` instead of a traditional for loop.
* Implementing a custom iterator function using `Symbol.iterator` and `yield`.
* Utilizing WebAssembly (WASM) for optimized performance.
* Leveraging Just-In-Time (JIT) compilation or other language optimizations.

Keep in mind that these alternatives might not be directly comparable to the original Map vs For Loop benchmark, but they could offer alternative approaches to solving similar problems.

Related benchmarks:

Map vs For Loop 2 (version: 2)

Comparing performance of: Map vs For Loop

Created: 7 years ago by: Registered User

Jump to the latest result

Map

For Loop

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):