Benchmark: indexOf vs map - MeasureThat.net

Script Preparation code:

function hasWithIndexOf(needle, haystack) {
	return haystack.indexOf(needle) !== -1;
}

function hasWithMapForEach(needle, haystack) {
	var map = {};
	haystack.forEach(item => map[item] = true);
	return map[needle];
}

function hasWithMapLoop(needle, haystack) {
	var map = {};
	for (var i=0, len=haystack.length; i<len; ++i) {
    	map[haystack[i]] = true;
    }
	return map[needle];
}
                     
var testArray = ['001', '002', '003', '004', '005', '006', '007', '008', '009', '010', '011', '012', '013', '014', '015', '016', '017', '018', '019', '020'];

Tests:

indexOf
for (var i=0; i<100; ++i) { hasWithIndexOf('000', testArray); }
map with forEach
for (var i=0; i<100; ++i) { hasWithMapForEach('000', testArray); }
map with loop
for (var i=0; i<100; ++i) { hasWithMapLoop('000', testArray); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
indexOf
map with forEach
map with loop

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what is being tested.

**Benchmark Definition**

The benchmark measures the performance of three different approaches to find an element in an array:

1. `indexOf`: Using the `indexOf()` method with a variable `needle`.
2. `map with forEach`: Creating a map (an object) from the array using the `forEach()` method and then searching for the `needle` in the map.
3. `map with loop`: Creating a map (an object) from the array using a traditional `for` loop and then searching for the `needle` in the map.

**Options Compared**

The three options are compared in terms of their performance, which is measured by the number of executions per second.

**Pros and Cons of Each Approach**

1. `indexOf`:
	* Pros: Simple, efficient, and widely supported.
	* Cons: May be slower for very large arrays due to the search algorithm's linear nature.
2. `map with forEach`:
	* Pros: Can be more memory-efficient than traditional loops, as it doesn't require creating an additional data structure (the map).
	* Cons: May be slower due to the overhead of creating and iterating over a map, especially for small arrays or arrays with limited iteration points.
3. `map with loop`:
	* Pros: Can be more efficient than the other two options for very large arrays, as it uses a traditional loop that can take advantage of CPU caching.
	* Cons: Requires more memory and code complexity compared to the other two options.

**Libraries Used**

None of the benchmark scripts explicitly use any libraries beyond built-in JavaScript functionality. However, the `map` function is part of the ECMAScript standard and is widely supported across most browsers.

**Special JS Features or Syntax**

The benchmark uses some advanced features in JavaScript:

* Arrow functions (`=>`) are used for concise method definitions.
* The `var` keyword is used with `i` to declare a variable that is scoped to the outer function.
* The `forEach()` method is used on the `testArray` to iterate over its elements.

**Other Considerations**

The benchmark is designed to provide a fair comparison of the three options, taking into account factors like memory usage and code complexity. However, it's worth noting that the results may vary depending on specific use cases or array characteristics.

**Alternative Approaches**

Some alternative approaches that could be considered for finding an element in an array include:

* Using `Array.prototype.find()` (a newer method introduced in ECMAScript 2015).
* Implementing a custom binary search algorithm.
* Using a more efficient data structure, such as a trie or a balanced tree.

However, these alternatives may not be represented in the provided benchmark definition.

Related benchmarks:

indexOf vs map (version: 0)

Comparing performance of: indexOf vs map with forEach vs map with loop

Created: 9 years ago by: Guest

Jump to the latest result

indexOf

map with forEach

map with loop

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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