Benchmark: Insert value at certain index in array

Insert value at certain index in array (version: 0) Benchmark.js

The goal is to test which is faster - combinations between Array.prototype.slice and Array.prototype.push methods or custom for-loop alternative in the context of inserting value at given index

Comparing performance of: `For-loop approach test vs Native functions test`

Created: 4 years ago by: Guest

Go to the latest result

Tests:

For-loop approach test
// Params: const arr = [1, 2, 3, 4]; const index = 3; const newItem = 5; // Steps: // 1. Create new array from the original one at given index let copy = []; for (let i = 0; i < index; i++) { copy[copy.length] = arr[i]; } // 2. Add new item to the copy copy[index] = newItem; // 3. Get the rest of the original array let rest = []; for (let i = index; i < arr.length; i++) { rest[rest.length] = arr[i]; } // 4. Merge the two arrays for (let i = 0; i < rest.length; i++) { copy[copy.length] = rest[i]; } // 5. Print the merged array console.log(copy);
Native functions test
// Params: const arr = [1, 2, 3, 4]; const index = 3; const newItem = 5; // Steps: // 1. Create new array from the original one at given index let start = arr.slice(0, index); // 2. Add new item to the copy start.push(newItem); // 3. Get the rest of the original array let end = arr.slice(index); // 4. Print the merged array console.log(start.concat(end));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
For-loop approach test
Native functions test

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:147.0) Gecko/20100101 Firefox/147.0

Browser/OS: Firefox 147 on Windows

View result in a separate tab

For-loop approach test

145K/s

Native functions test

142K/s

View exact numbers

Test name	Executions per second
✓ For-loop approach test	144,801 Ops/sec
Native functions test	142,317 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**What is being tested?**

The provided JSON represents a benchmark that tests two approaches to inserting a value at a certain index in an array:

1. **For-loop approach**: This involves creating a new array by iterating over the original array up to the insertion point, copying the elements before the insertion point, adding the new element, and then copying the elements after the insertion point.
2. **Native functions (Array.prototype.slice)**: This uses built-in JavaScript methods to create a new array by slicing the original array at two points: one before the insertion point and one after.

**Options being compared**

The benchmark compares the performance of these two approaches:

* For-loop approach
* Native functions (Array.prototype.slice)

**Pros and cons of each approach**

1. **For-loop approach**:
	* Pros:
		+ Control over the iteration process, allowing for optimization.
		+ Can be more readable for developers who are familiar with loops.
	* Cons:
		+ May be slower due to the overhead of explicit loop control.
		+ Requires more memory allocation (creating a new array).
2. **Native functions (Array.prototype.slice)**:
	* Pros:
		+ Faster execution speed, as it leverages optimized native code.
		+ More concise and expressive syntax for array manipulation.
	* Cons:
		+ Less control over the iteration process.
		+ May require more memory allocation (creating temporary arrays).

**Library used**

There is no explicit library mentioned in the benchmark definition or test cases. However, it's likely that the `console.log` function is used to print the results of the array manipulation.

**Special JS feature or syntax**

There are some special features and syntax used in this benchmark:

* The use of template literals (`// Params:\r\nconst arr = [1, 2, 3, 4];`) for string interpolation.
* The use of `for` loops (specifically, a traditional loop with index variables) to iterate over the array.

**Other alternatives**

If the developers wanted to explore alternative approaches, they might consider:

* Using other built-in JavaScript methods, such as `Array.prototype.splice` or `Array.prototype.concat`, to manipulate the array.
* Implementing their own custom algorithm for inserting elements at a specific index.
* Using libraries like Lodash or Ramda, which provide functional programming utilities and optimized implementations of common operations.

Keep in mind that these alternatives would likely require significant changes to the benchmark definition and test cases.