Benchmark: load indices 3 - MeasureThat.net

Script Preparation code:

let size = 100;
let indices = [];

Tests:

simple reverse for
indices = [], size = 100; for (i = size; i--; ) { indices[i] = i; }
reverse while
indices = [], i = size; while (i--) indices[i] = i;
for-push
indices = []; for (i = 0; i <= size; i++) { indices.push(i); }
for
indices = []; for (i = 0; i < size; i++) { indices[i] = i; }
reverse for
indices = []; for (i = size; i > -1; i--) { indices[i] = i; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
simple reverse for
reverse while
for-push
for
reverse for

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/117.0.0.0 Safari/537.36

Browser/OS: Chrome 117 on Windows

View result in a separate tab

Test name	Executions per second
simple reverse for	94976.6 Ops/sec
reverse while	60132.7 Ops/sec
for-push	30754.7 Ops/sec
for	30913.3 Ops/sec
reverse for	61105.8 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 of each approach, and other considerations.

**Benchmark Definition**

The JSON defines two types of benchmarks: "Script Preparation Code" and "Html Preparation Code". The script preparation code is used to prepare the JavaScript environment before running the benchmark. In this case, it's a simple assignment of variables:

`let size = 100;`
`let indices = [];`

This code sets up an array `indices` with a length of 100.

The html preparation code is empty (`null`), which means no additional HTML code is being prepared.

**Individual Test Cases**

Each test case defines a JavaScript function that fills the `indices` array. There are four different approaches:

1. **Simple Reverse For**: `for (i = size; i--; ) indices[i] = i;`
2. **Reverse While**: `while (i--) indices[i] = i;`
3. **For-Push**: `for (i = 0; i <= size; i++) {indices.push(i);}`
4. **Simple For**: `for (i = 0; i < size; i++) {indices[i] = i;}`

**Comparison of Approaches**

Here's a brief explanation of each approach:

* **Simple Reverse For**: This approach uses a traditional for loop and decrements the index variable (`i`) until it reaches zero. It's a simple and straightforward way to fill the array.
* **Reverse While**: This approach uses a while loop with a decrementing index variable (`i`). However, it can lead to issues when the array is filled from the end towards the beginning, as the index `i` will become negative.
* **For-Push**: This approach uses a for loop and pushes elements onto the array using the `push()` method. This approach can be slower than assigning elements directly to the array, especially for large arrays.
* **Simple For**: This approach uses a traditional for loop with an incrementing index variable (`i`). It's similar to the simple reverse for but avoids the issue of negative indices.

**Pros and Cons**

Here are some pros and cons of each approach:

* **Simple Reverse For**: Pros: Simple, straightforward, and easy to understand. Cons: Can lead to issues with negative indices.
* **Reverse While**: Pros: None notable. Cons: Can lead to issues with negative indices.
* **For-Push**: Pros: None notable. Cons: Can be slower than assigning elements directly to the array.
* **Simple For**: Pros: Avoids negative indices, easy to understand. Cons: None notable.

**Library and Special Features**

There are no libraries used in this benchmark, as it's a simple JavaScript microbenchmark.

No special features or syntax are being tested, as all approaches use standard JavaScript syntax.

**Other Alternatives**

Some alternative approaches that could be tested include:

* Using an array constructor (`new Array(size)` ) to create the `indices` array.
* Using a spread operator (`[...Array(size).keys()]`) to fill the `indices` array.
* Using a `for...of` loop with an iterator (not used in this benchmark).
* Using a `Set` or other data structure instead of an array.

These alternatives could provide additional insights into the performance characteristics of different JavaScript approaches.

Related benchmarks:

load indices 3 (version: 1)

Comparing performance of: simple reverse for vs reverse while vs for-push vs for vs reverse for

Created: 3 years ago by: Registered User

Jump to the latest result

simple reverse for

reverse while

for-push

for

reverse for

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):