Hi,

I am just starting to use the alphahull package on a mac (OS:10.6.8 ) with
R(2.14.1) but I have come across a small problem which I cannot seem to
replicate using the toy examples from the package.

I have approx 130,000 data locations in European waters and I want to use
alpha hull to provide me with polygons defining where the bounds of the
data are (eg: how far into the Atlantic they go).  The image I get when i
plot the ahull object contains what appears to be a continuous set of arcs
around the outer edge of my area and one for each of the British Isles.
However, on closer inspection of the ahull.obj$arcs dataframe there are
more than three closed loops.  The British Isles holes are described as one
loop each but the outer loop gets split into smaller chunks thus not
defining the whole region as one.  I realise my description is not great
but has anyone else come across this problem?  I wonder is it to do with
volume of data?

Any help would be greatly appreciated.

Many Thanks,
Lindesay



-------------------------------------------------------------------
Lindesay Scott-Hayward
Centre for Research into Ecological and
Environmental Modelling (CREEM),
The Observatory, University of St Andrews,
Fife KY16 9LZ  Scotland
Tel: +44 (0) 1334 461824

The University of St Andrews is a charity registered in Scotland : No
SC013532

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