Benchmark: Substring from second and from fifth character, within 10 characters

Script Preparation code:

var set = [];
for (var idx = 0; idx < 1000; idx++)
{
  set.push("_" + (Math.random().toString().substring(2)));
}

Tests:

Normal access
var asd = null; for (var idx = 0; idx < set.length; idx++) { asd = set[idx]; }
Substring from second character
var asd = null; for (var idx = 0; idx < set.length; idx++) { asd = set[idx].substring(1); }
Substring from fifth character
var asd = null; for (var idx = 0; idx < set.length; idx++) { asd = set[idx].substring(1); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Normal access
Substring from second character
Substring from fifth character

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.192 Safari/537.36

Browser/OS: Chrome 88 on Windows

View result in a separate tab

Test name	Executions per second
Normal access	4324.8 Ops/sec
Substring from second character	4265.6 Ops/sec
Substring from fifth character	4205.1 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 provided benchmark definition and individual test cases.

**Benchmark Definition:**
The benchmark measures the performance of JavaScript code that extracts substrings from a string array using different methods. The script preparation code generates an array of 1000 strings, each with a random substring of length 2 (starting from the second character).

**Script Preparation Code:**
```javascript
var set = [];
for (var idx = 0; idx < 1000; idx++) {
  set.push("_" + (Math.random().toString().substring(2)));
}
```
This code generates an array of 1000 strings, each with a random character followed by an underscore. The `Math.random()` function is used to generate random numbers.

**Html Preparation Code:**
There is no HTML preparation code provided, which suggests that the benchmark only tests JavaScript performance and does not consider DOM manipulation or rendering.

**Individual Test Cases:**
The benchmark has three test cases:

1. **Normal access:**
```javascript
var asd = null;
for (var idx = 0; idx < set.length; idx++) { asd = set[idx]; }
```
This code iterates through the `set` array and assigns each string to a variable named `asd`. The purpose of this test is to measure the performance of accessing an element in an array.

2. **Substring from second character:**
```javascript
var asd = null;
for (var idx = 0; idx < set.length; idx++) { asd = set[idx].substring(1); }
```
This code iterates through the `set` array and extracts the substring starting from the second character of each string. The purpose of this test is to measure the performance of extracting a substring.

3. **Substring from fifth character:**
```javascript
var asd = null;
for (var idx = 0; idx < set.length; idx++) { asd = set[idx].substring(1); }
```
This code is identical to the previous test case, but with an incorrect index (it should be `4` instead of `1`) in the `substring()` method.

**Library:**
The benchmark uses no external libraries. The performance tests are implemented using standard JavaScript syntax and built-in data structures like arrays.

**Special JS Features/Syntax:**
There are no special features or syntax used in this benchmark. It only relies on basic JavaScript operations and data structures.

**Pros and Cons of Different Approaches:**

* **Normal access:** This approach is straightforward and efficient, as it simply assigns each element to a variable without any additional overhead.
	+ Pros: Simple, fast
	+ Cons: May not be the most efficient way to iterate through an array, depending on the JavaScript engine used.
* **Substring from second character:** This approach extracts a substring from each string, which may incur some overhead due to the creation of new strings or DOM elements (if applicable).
	+ Pros: Can be useful for testing substring extraction algorithms
	+ Cons: May not be efficient if the strings are large, as it creates additional objects.
* **Substring from fifth character:** This approach is incorrect and should not be used. It may cause errors or unexpected behavior in the JavaScript engine.

**Other Alternatives:**
There are other ways to benchmark JavaScript performance, such as:

* Using a framework like Benchmark.js or js-benchmark
* Creating a custom benchmarking library using Node.js and a testing framework like Jest or Mocha
* Utilizing web workers or parallel processing techniques to measure the performance of multithreaded JavaScript code.

These alternatives can provide more comprehensive testing scenarios, better isolation, and higher accuracy in measuring JavaScript performance.

Related benchmarks:

Substring from second and from fifth character, within 10 characters (version: 0)

Comparing performance of: Normal access vs Substring from second character vs Substring from fifth character

Created: 3 years ago by: Guest

Jump to the latest result

Normal access

Substring from second character

Substring from fifth character

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):