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index vs lastindexofasdf
(version: 0)
asdf
Comparing performance of:
lastIndexOf vs indexOf
Created:
4 years ago
by:
Guest
Jump to the latest result
Script Preparation code:
var a = [...Array(7200)].map((x, i) => i);
Tests:
lastIndexOf
var n = a.lastIndexOf(7000);
indexOf
var n = a.indexOf(7000);
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
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Test case name
Result
lastIndexOf
indexOf
Fastest:
N/A
Slowest:
N/A
Latest run results:
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Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
I'll break down the benchmark and its results to help you understand what's being tested. **Benchmark Overview** The benchmark is comparing two JavaScript methods: `indexOf` and `lastIndexOf`. The test case uses an array of 7200 elements, generated using `Array.from()` and a map function that returns the index of each element. The purpose of this setup is to create a large dataset with a specific value (7000) at a certain position. **Options Compared** The two options being compared are: 1. `indexOf`: Returns the first occurrence of a specified value in an array. 2. `lastIndexOf`: Returns the last occurrence of a specified value in an array. **Pros and Cons of Each Approach** * `indexOf`: + Pros: Faster for arrays with many elements that don't contain the target value, as it stops searching as soon as it finds the first match. + Cons: May be slower when the target value is at the end of the array, as it needs to search from the beginning. Additionally, `indexOf` has a lower detection threshold than `lastIndexOf`, meaning that smaller arrays with more occurrences of the target value will favor `indexOf`. * `lastIndexOf`: + Pros: Faster for arrays with many elements that do contain the target value, as it only needs to traverse from the end towards the beginning. + Cons: May be slower when the array is small and contains multiple occurrences of the target value, due to the additional overhead. **Library Used** None explicitly mentioned in the provided benchmark definitions. However, both methods use built-in JavaScript array functions. **Special JS Features/Syntax (Not Applicable)** No special features or syntax are being tested in this benchmark. **Other Alternatives** If you were to implement your own version of this benchmark, you might consider using other libraries or modules that provide optimized string search algorithms, such as: * `String.prototype.indexOf()`: Similar to the built-in method, but optimized for performance. * `String.prototype.lastIndexOf()`: Similar to the built-in method, but optimized for performance. Alternatively, you could use third-party libraries like: * Lodash (`lodash.lastIndexOf()`): Provides a high-performance implementation of `lastIndexOf`. * Fast String Search (FSS) (`fast-string-search`): A highly optimized library for string search algorithms, including `indexOf` and `lastIndexOf`. Keep in mind that these alternatives might introduce additional dependencies or complexity to your benchmark.
Related benchmarks:
index vs lastindexof empty
index vs lastindexof (for right biased values)
findIndex vs IndexOf + map
findIndex vs indexOf - JavaScript performance v2
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