Toggle navigation
MeasureThat.net
Create a benchmark
Tools
Feedback
FAQ
Register
Log In
Array.from vs new Array
(version: 0)
Comparing performance of:
Array.from vs new Array
Created:
5 years ago
by:
Guest
Jump to the latest result
Tests:
Array.from
Array.from({ length: 4 }, () => new Array(4).fill(0));
new Array
new Array(4).fill(0).map(() => new Array(4).fill(0));
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
Fork
Test case name
Result
Array.from
new Array
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):
Let's break down the provided benchmark and explain what's being tested. **Benchmark Definition** The benchmark is defined as comparing two approaches to create an array of arrays: `Array.from` versus creating an array with `new Array`. In JavaScript, both methods are used to achieve similar results. However, they differ in how they're implemented and might have varying performance characteristics. **Options being compared** Two options are being compared: 1. **`Array.from({ length: 4 }, () => new Array(4).fill(0))`**: This method uses the `Array.from()` method to create an array of arrays. The callback function generates four arrays with zeros, and `Array.from()` collects these arrays into a single array. 2. **`new Array(4).fill(0).map(() => new Array(4).fill(0))`**: This method uses the `new Array()` constructor to create an empty array, fills it with zeros using `fill(0)`, and then maps over the array to generate four inner arrays. **Pros and cons of each approach** 1. **`Array.from()`**: * Pros: concise and expressive syntax, can be easily modified or extended. * Cons: might incur additional overhead due to the creation of an intermediate array. 2. **`new Array()`**: * Pros: allows for fine-grained control over the inner arrays (e.g., using `map()`). * Cons: more verbose and less concise, requires explicit typing. **Library usage** Neither method relies on a specific library. However, it's worth noting that some JavaScript engines might optimize or specialize these methods in certain contexts. **Special JS features or syntax** No special JavaScript features or syntax are being tested here; the focus is solely on comparing two simple array creation methods. **Other alternatives** For creating arrays of arrays, other approaches exist: 1. **`Array.prototype.map()`**: Similar to `new Array()`, but can be used on existing arrays. 2. **`Array.from()` with a custom function**: Can generate arrays with specific structures or properties. 3. **Native array creation methods**: Some browsers and environments provide native methods for creating arrays, like `Array.create()`. Keep in mind that the performance characteristics of these alternatives might vary depending on the JavaScript engine and environment. **Benchmark preparation code** The provided benchmark preparation code is minimal, consisting only of an empty `Script Preparation Code` field. In a real-world scenario, this code would typically include any necessary setup or initialization for the benchmark, such as generating test data or configuring performance metrics.
Related benchmarks:
Array.from() vs new Array()
Array.from() vs new Array() - empty
Array.from({ length: n }) vs new Array(n)
Array.from() vs new A
Array.from() vs new Array() vs []
Comments
Confirm delete:
Do you really want to delete benchmark?