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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.lang.javascript
Subject: Re: Picture colors decreasing script.
Date: Thu, 04 Mar 2021 02:07:30 +0000
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"Michael Haufe (TNO)" <tno@thenewobjective.com> writes:

> On Wednesday, March 3, 2021 at 2:53:26 PM UTC-6, Thomas 'PointedEars' Lahn wrote:
>> Michael Haufe (TNO) wrote: 
>> > <https://jsbench.me/ulkltk1xpk>
>> Fascinating; slicing is 93.08 % slower than direct access. But why?
>
> Given the steps slice takes, this should not be surprising:
>
> <https://tc39.es/ecma262/#sec-array.prototype.slice>
>
> Direct access is O(1)
>
> `slice` is O(N) where N is end - start

Isn't that O(1) for the case in question?  (Big O might be too crude a
measure for this.)

> Thus an order of magnitude worse.

-- 
Ben.