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Topic: How to find a bounding line?
Replies: 39   Last Post: Jul 12, 2013 5:39 AM

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LudovicoVan

Posts: 3,206
From: London
Registered: 2/8/08
Re: How to find a bounding line?
Posted: Jul 11, 2013 4:13 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

"quasi" <quasi@null.set> wrote in message
news:sv3ut81468r32190odno2jc1pnei0lmlit@4ax.com...
> ols6000 wrote:
>

>>One further thing to keep in mind: a method in which you select
>>the best of N-1 lines is O(N^2), because calculation of the sum
>>for each line is O(N). That means such a method isn't practical.

>
> Good point.
>
> The most efficient algorithm proposed so far has complexity O(N)
> _times_ the complexity of a distance sum calculation.
>
> However, a distance sum calculation by its very nature is O(N).
> so if each one of the distance sum calculations has to be done
> separately, and if each one is O(N), then, as you indicate, the
> whole task is O(N^2).
>
> It seems unlikely that you can do better.


As already noted, we can indeed do better, namely O(N+N), as there is no
need to recalculate the cost function from scratch at each step.

Julio

> But do you now at least acknowledge my previous claim that there
> is an optimal bounding line which passes through two consecutive
> points of the convex hull?





Date Subject Author
7/7/13
Read How to find a bounding line?
Woody
7/7/13
Read Re: How to find a bounding line?
Scott Berg
7/7/13
Read Re: How to find a bounding line?
Peter Percival
7/7/13
Read Re: How to find a bounding line?
Woody
7/7/13
Read Re: How to find a bounding line?
quasi
7/7/13
Read Re: How to find a bounding line?
quasi
7/8/13
Read Re: How to find a bounding line?
quasi
7/8/13
Read Re: How to find a bounding line?
Woody
7/8/13
Read Re: How to find a bounding line?
quasi
7/8/13
Read Re: How to find a bounding line?
LudovicoVan
7/8/13
Read Re: How to find a bounding line?
LudovicoVan
7/10/13
Read Re: How to find a bounding line?
Woody
7/10/13
Read Re: How to find a bounding line?
quasi
7/8/13
Read Re: How to find a bounding line?
Leon Aigret
7/8/13
Read Re: How to find a bounding line?
Woody
7/10/13
Read Re: How to find a bounding line?
Leon Aigret
7/10/13
Read Re: How to find a bounding line?
Leon Aigret
7/10/13
Read Re: How to find a bounding line?
Woody
7/10/13
Read Re: How to find a bounding line?
RGVickson@shaw.ca
7/10/13
Read Re: How to find a bounding line?
Woody
7/10/13
Read Re: How to find a bounding line?
quasi
7/7/13
Read Re: How to find a bounding line?
quasi
7/7/13
Read Re: How to find a bounding line?
quasi
7/7/13
Read Re: How to find a bounding line?
quasi
7/8/13
Read Re: How to find a bounding line?
William Elliot
7/8/13
Read Re: How to find a bounding line?
Peter Percival
7/8/13
Read Re: How to find a bounding line?
quasi
7/11/13
Read Re: How to find a bounding line?
Woody
7/11/13
Read Re: How to find a bounding line?
quasi
7/11/13
Read Re: How to find a bounding line?
LudovicoVan
7/11/13
Read Re: How to find a bounding line?
quasi
7/11/13
Read Re: How to find a bounding line?
Leon Aigret
7/11/13
Read Re: How to find a bounding line?
Woody
7/11/13
Read Re: How to find a bounding line?
Leon Aigret
7/12/13
Read Re: How to find a bounding line?
Woody
7/12/13
Read Re: How to find a bounding line?
Leon Aigret
7/11/13
Read Re: How to find a bounding line?
Woody
7/12/13
Read Re: How to find a bounding line?
quasi
7/12/13
Read Re: How to find a bounding line?
Woody
7/12/13
Read Re: How to find a bounding line?
quasi

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