Benchmark: Data normalization

Script Preparation code:

var data = Object.entries({ ...Array.from(Array(10000).keys()) });

Tests:

reduce with same obj
data.reduce((map, [price, vol]) => { map[price] = vol; return map; }, {});
fromEntries
Object.fromEntries(data);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
reduce with same obj
fromEntries

Fastest: N/A

Slowest: N/A

Latest run results:

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

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Let's break down the provided JSON data and explain what's being tested, compared, and discussed.

**Benchmark Definition**
The benchmark is focused on measuring the performance difference between two approaches: reducing an array of objects into a single object using `Array.prototype.reduce()` and creating the same object using `Object.fromEntries()`. The input data consists of 10,000 key-value pairs stored in an array of arrays, where each inner array contains a price and a volume.

**Script Preparation Code**
The script preparation code defines the input data:
```javascript
var data = Object.entries({ ...Array.from(Array(10000).keys()) });
```
This creates an object with 10,000 key-value pairs, where each key is a unique integer from 0 to 9,999 and the corresponding value is `undefined`.

**Html Preparation Code**
There is no HTML preparation code provided.

**Options Being Compared**

The two options being compared are:

1. **`Array.prototype.reduce()`**: This method applies a reduction function to each element in the array and accumulates a result. In this case, it's used to create an object with price as keys and volume as values.
2. **`Object.fromEntries()`**: This method creates a new object from an iterable of key-value pairs.

**Pros and Cons**

* `Array.prototype.reduce()`: Pros:
	+ Can handle non-integer keys (arrays can be used as keys).
	+ May be more efficient for large datasets due to its ability to accumulate the result.
* Cons:
	+ Requires iterating over the entire array, which may lead to slower performance for very large datasets.
	+ Can be less readable than `Object.fromEntries()` for complex operations.
* `Object.fromEntries()`: Pros:
	+ Creates a new object with keys and values from an iterable of key-value pairs.
	+ More readable and concise than `Array.prototype.reduce()`.
* Cons:
	+ Limited to only using iterables as input (arrays, maps, sets).
	+ May be less efficient for very large datasets due to the creation of multiple intermediate arrays.

**Library**
In this benchmark, there are no external libraries being used.

**Special JavaScript Features or Syntax**

There are no special features or syntax mentioned in the provided code. The standard JavaScript `reduce()` and `Object.fromEntries()` methods are used without any additional options or customizations.

**Other Alternatives**

For comparison purposes, other alternatives to these two options could include:

* Using `Array.prototype.forEach()` and a callback function to iterate over the array and create an object.
* Using `Array.prototype.map()` to create an array of key-value pairs and then using `Object.fromEntries()` or `reduce()` to create the final object.

However, it's worth noting that these alternatives would likely introduce more overhead due to additional memory allocations and operations.

Related benchmarks:

Data normalization (version: 0)

Comparing performance of: reduce with same obj vs fromEntries

Created: 3 years ago by: Guest

Jump to the latest result

reduce with same obj

fromEntries

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):