Hi,
I'm not sure if this is relevant. I thought other
software packages give you the option to get the
location as 1) centre of gravity; 2) arithmetic
mean of x and y; 3) drop the farthest point and
recalculate the remaining ; 4) drop the point
that changes the area greatly and recalculate; 5)
use the median of x and y as the location; and other methods.
Kail
At 11:37 PM 8/26/2010 +0200, you wrote:
Hi List,
I'm forwarding our correspondence with Vaclav, maybe someone could have any
thoughts. In the situation presented on the screenshots, there was three
bearings building a triang. Then adding the fourth bearing (the point on the
nord) doesn't change the polygon geometry, but moves the location as it's
computed as a center of gravity. For me it's the best solution, but maybe
anyone have better ideas?
B.
From: Borys Jurgiel <[email protected]>
To: Václav Åehák <[email protected]>
Subject: Re: [AniMov] new plugins are coming
Date: Thu, 26 Aug 2010 23:29:29 +0200
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Dnia czwartek 26 sierpnia 2010 o 22:24:23 Václav Åehák napisaÅ(a):
> Hi,
>
> I tried to modify your test data by adding a new bearing to the subset
> (fix id) 5 using "Add feature" button in QGIS and expected the result
> area to change from a triangle to square but it did not happen. It
> looks like my line is drawn OK but is not included in the area
> computation. Please see attached data. Do you know what's wrong?
Look at the screenshot. The area is computed as a convex hull, and the
location is computed as a center of gravity. The red location is computed
using the 4 bearings, while the green one is computed from the old 3 bearings.
Also in the attribute table of the compuyed location there's n=5, what is a
number of used intersections.
So all is ok, but maybe the algorithm is not the best solution. Do you have a
better idea?
B.
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