Benchmark: demo21312312312 - MeasureThat.net

Tests:

keys
Array.from(new Array(30).keys())
length
Array.from(Array.from({ length: 30 }).keys())
length map
Array.from({ length: 30 }).map((_, i) => i)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
keys
length
length map

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.

**Overview of the Benchmark**

The provided JSON represents a JavaScript microbenchmark, specifically designed to compare the performance of different approaches for creating arrays with a specified length or iterating over an array.

**Benchmark Definition and Script Preparation Code**

The benchmark definition is stored in the `Benchmark Definition` field of each test case. For example:

* "Array.from(new Array(30).keys())"
* "Array.from(Array.from({ length: 30 }).keys())"
* "Array.from({ length: 30 }).map((_, i) => i)"

The script preparation code is empty for this benchmark, which means that no additional setup or initialization code needs to be executed before running the benchmark.

**Options Compared**

Three different approaches are being compared:

1. **`Array.from(new Array(30).keys())`**: This approach uses the `Array.prototype.keys()` method to get an array of keys from a new array created with `new Array(30)`.
2. **`Array.from(Array.from({ length: 30 }).keys())`**: This approach uses the `Array.from()` method twice, first creating a new array with `length: 30`, and then getting an array of keys from that array using `Array.prototype.keys()`.
3. **`Array.from({ length: 30 }).map((_, i) => i)`**: This approach uses the `Array.prototype.map()` method to create a new array with values generated by mapping over an existing array created with `{ length: 30 }`.

**Pros and Cons of Each Approach**

Here's a brief analysis of each approach:

1. **`Array.from(new Array(30).keys())`**:
	* Pros: Simple, concise, and efficient.
	* Cons: May be slower than other approaches due to the overhead of creating an array with `new Array(30)`.
2. **`Array.from(Array.from({ length: 30 }).keys())`**:
	* Pros: Reduces memory allocation overhead compared to the first approach.
	* Cons: More complex and harder to read, as it involves two calls to `Array.from()`.
3. **`Array.from({ length: 30 }).map((_, i) => i)`**:
	* Pros: Efficiently generates an array with values from 0 to 29 using the `map()` method.
	* Cons: Requires understanding of how `map()` works and may be less readable than other approaches.

**Other Considerations**

* The use of `Array.from()` is a modern JavaScript feature, which means that older browsers or environments might not support it. This could affect the benchmark results.
* The `map()` method can be slower for small arrays due to its overhead, but becomes more efficient as the array size increases.

**Alternative Approaches**

Other possible approaches for creating an array with a specified length or iterating over an array include:

1. **Using `Array.prototype.fill()`**: This approach involves using the `fill()` method to create an array with a specific value repeated for a given length.
2. **Using a for loop**: This approach involves using a traditional `for` loop to iterate over a range of numbers and push values onto an array.
3. **Using `Array.from()` with a callback function**: This approach involves passing a callback function to `Array.from()` to generate an array with specific values.

However, these alternatives might not be as efficient or concise as the approaches being compared in this benchmark.

Related benchmarks:

demo21312312312 (version: 0)

Comparing performance of: keys vs length vs length map

Created: 7 years ago by: Guest

Jump to the latest result

keys

length

length map

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):