Benchmark: for vs map - MeasureThat.net

Script Preparation code:

var array = [1, 4, 9, 16];

Tests:

map
var map = array.map(x => x * 2);
for
var map = []; for(let i = 0; i < array.length; i++) { map.push(array[i] * 2); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
map
for

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Mac OS X 10.15.7

View result in a separate tab

map

24.2M/s

for

18.4M/s

View exact numbers

Test name	Executions per second
✓ map	24,151,866 Ops/sec
for	18,433,222 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, the different approaches compared, their pros and cons, and other considerations.

**Benchmark Overview**

The benchmark is designed to compare the performance of two common ways to multiply an array of numbers: using the `map()` function or a traditional `for` loop. The test uses a simple example where an array of numbers is multiplied by 2.

**Script Preparation Code**

The script preparation code defines a single variable, `array`, which contains an array of numbers: `[1, 4, 9, 16]`.

**Html Preparation Code**

There is no HTML preparation code provided in this benchmark.

**Benchmark Definition**

The benchmark definition provides the two test cases:

1. **`map`**: This test case uses the `map()` function to multiply each number in the array by 2.
```javascript
var map = array.map(x => x * 2);
```
2. **`for`**: This test case uses a traditional `for` loop to iterate over the array and push the multiplied values into an empty array `map`.
```javascript
var map = [];
for (let i = 0; i < array.length; i++) {
    map.push(array[i] * 2);
}
```
**Library: None**

There is no external library used in this benchmark.

**Special JS Feature/Syntax: None**

Neither of the test cases uses any special JavaScript features or syntax, such as async/await, Promises, or closures.

**Pros and Cons of Approaches**

Here's a brief summary of the pros and cons of each approach:

1. **`map()`**: Pros:
	* More concise and expressive.
	* Easier to read and maintain.
2. **`for`**: Pros:
	* Provides more control over the iteration process (e.g., ability to break out of loops).
	* Can be more efficient in certain scenarios (e.g., when using a cache).

Cons:

1. **`map()`**:
	* May have higher overhead due to function calls.
2. **`for`**:
	* Requires explicit loop control and may lead to more code.

**Other Considerations**

When choosing between `map()` and a traditional `for` loop, consider the following factors:

* Readability: If you need to understand the intent of your code clearly, `map()` might be a better choice.
* Performance: In general, `map()` can be faster due to its optimized implementation. However, this may vary depending on the specific use case and the browser/interpreter being used.
* Control: If you require more control over the iteration process or need to handle edge cases explicitly, a traditional `for` loop might be a better fit.

**Alternatives**

If you're looking for alternative approaches to multiplication, consider:

1. **Arithmetic operators**: You can use arithmetic operators (e.g., `*`) directly on arrays using array methods like `every()` or `forEach()`.
2. **Array comprehension**: Some modern JavaScript engines support array comprehensions, which allow you to define concise and expressive loops.

Keep in mind that these alternatives might not be suitable for all use cases, especially when compared to the traditional `for` loop or `map()` approach.

for vs map (version: 0)

Comparing performance of: `map vs for`

Created: 6 years ago by: Guest

Go to the latest result

map

for

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

for vs map (version: 0)

Comparing performance of: map vs for

Created: 6 years ago by: Guest

Go to the latest result

map

for

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `map vs for`