| findborderquads {CTFS} | R Documentation |
Identified neighboring quadrates from a given quadrate number,
refered to as the index. Returns the quadrat numbers within a given distance.
findborderquads(index, dist = 20, gridsize = 20, plotdim = c(1000, 500))
index |
quadrate number, between 0 and 1249 in the standard plot |
dist |
distance in m within which the neighboring quadrates are located. Distance is measured from any side of the index quadrate. |
gridsize |
side of the square quadrate, 20 x 20m by default |
plotdim |
dimensions of the plot: east-west 1000m and north-south 500m |
A quadrate is considered a neighbor if
any part of it lies within dist of the center of the quadrate
indicated by index. At the minimum the quadrates that share
edges, including corners, will always be returned. This is 8
quadrates. The index quadrate is NOT returned. All values
>=0 and <20 give the same 8 quadrates for a centrally located
quadrate.
As dist increases, more quadrates can be included up to the
edges of the plot. For gridsize=20, 8 quadrates are
neighbors up to dist<20. This doesn't change until
dist >= 20, then there are 24 neighbors, etc.
This function depends upon index.to.rowcol to identify
the neighboring quadrates.
Returns a vector of numbers, the quadrate indices for all surrounding quadrates.
Rick Condit
## Not run: sort(findborderquads(231,dist=10)) sort(findborderquads(231,dist=20)) sort(findborderquads(231,dist=0)) ## End(Not run)