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Re: HASH question [message #75447 is a reply to message #75367]

Tue, 08 March 2011 07:56

penteado
Messages: 866
Registered: February 2018

Senior Member
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On Mar 8, 12:05 pm, Paolo <pgri...@gmail.com> wrote:
> well i never thought of "where" as being particularly awkward
> inefficient, yes if used a lot
> alternatively the stars could be sorted alphabetically by ID
> to allow for fast search

Sorted arrays would not be any faster with where(). It would take a
custom search function to do it.

>> the arrays cannot have elements dynamically added or removed,
>
> you can do concatenatation to add, say, another bunch of 100 stars
> stars can be removed by setting the ID to the empty string or
> using array concatenation yet again
> not extremly efficient but works

Yes, but it is awkward. One big reason for using dynamic containers is
to avoid all this juggling, allowing one to just do the operation one
is interested in doing. Like just adding an element. The same goes for
retrieving or setting an element from a hash: one can just do the
access, without having to do searches. That way code is not
complicated to do a conceptually simple task.

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[Message index]

		HASH question By: Gray on Sat, 05 March 2011 05:41
		Re: HASH question By: penteado on Tue, 08 March 2011 10:15
		Re: HASH question By: pgrigis on Tue, 08 March 2011 10:12
		Re: HASH question By: penteado on Tue, 08 March 2011 07:56
		Re: HASH question By: David Fanning on Tue, 08 March 2011 07:11
		Re: HASH question By: pgrigis on Tue, 08 March 2011 07:05
		Re: HASH question By: Gray on Tue, 08 March 2011 04:23
		Re: HASH question By: chris_torrence@NOSPAM on Mon, 07 March 2011 13:38
		Re: HASH question By: penteado on Mon, 07 March 2011 13:05
		Re: HASH question By: penteado on Mon, 07 March 2011 13:02
		Re: HASH question By: chris_torrence@NOSPAM on Mon, 07 March 2011 13:00
		Re: HASH question By: pgrigis on Mon, 07 March 2011 12:32
		Re: HASH question By: Jeremy Bailin on Mon, 07 March 2011 11:15

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