Benchmark: Array vs. object

Script Preparation code:

var obj = {
    1: true,
    2: false,
    3: true,
    4: false
};
var arr = [1, 3];

Tests:

Object lookup
obj[1] !== undefined
Array lookup
arr.includes(1)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object lookup
Array lookup

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

LLMs can make mistakes. Check important info.

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

**Benchmark Definition**

The provided JSON represents a JavaScript microbenchmark on MeasureThat.net. The benchmark is called "Array vs. object" and has two test cases: "Object lookup" and "Array lookup". This means that users can create and run their own JavaScript benchmarks to compare the performance of accessing elements in arrays versus objects.

**Options Compared**

The two options being compared are:

1. Object lookups (`obj[1] !== undefined`)
2. Array lookups (`arr.includes(1)`)

These two options differ in how they access an element within a data structure.

* Object lookup: Accessing an object's property using square brackets `[]` (e.g., `obj[1]`). This method uses the property name as an index.
* Array lookup: Using the `includes()` method to check if an element is present in an array (`arr.includes(1)`).

**Pros and Cons**

Here are some pros and cons of each approach:

* Object lookups:
	+ Pros:
		- Can be faster for sparse objects with few keys.
		- Less memory usage, as only the property name is stored.
	+ Cons:
		- May be slower for dense arrays or when accessing many properties.
		- Requires more code to access individual elements (e.g., `obj[1]`).
* Array lookups:
	+ Pros:
		- Faster for dense arrays with many elements.
		- More concise syntax, making it easier to access elements (e.g., `arr.includes(1)`).
	+ Cons:
		- May be slower for sparse objects or when accessing few properties.
		- Requires more memory, as the array needs to store all elements.

**Library and Syntax**

No specific libraries are mentioned in the benchmark definition. However, the test cases use JavaScript's built-in `Object` and `Array` prototypes.

The syntax used is standard JavaScript syntax, without any advanced features like async/await or destructuring.

**Other Considerations**

When choosing between object lookups and array lookups, consider the following:

* If you need to access many elements in a sparse object, an object lookup might be faster.
* For dense arrays with many elements, an array lookup is usually faster.
* When working with dynamic data structures, using `includes()` can simplify your code.

**Alternatives**

MeasureThat.net offers other benchmarking options, including:

1. Microbenchmarking: Similar to the "Array vs. object" benchmark, but allows users to create custom benchmarks.
2. Real-world benchmarking: Measures the performance of real-world scenarios, such as rendering a web page or processing user input.
3. Machine learning and AI benchmarking: Tests the performance of machine learning algorithms and AI models.

Please note that MeasureThat.net's focus is on JavaScript microbenchmarking, so these alternatives might not be directly related to object vs. array lookups.

Related benchmarks:

Array vs. object (version: 0)

Comparing performance of: Object lookup vs Array lookup

Created: 3 years ago by: Guest

Jump to the latest result

Object lookup

Array lookup

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):