NvMConvexHull {cheddar} | R Documentation |
Compute the convex hull around log-transformed $N$ versus $M$ data.
NvMConvexHull(community)
community |
an object of class |
Returns the points and area of the minimum convex hull (a polygon in log10-transformed numerical abundance versus log10-transformed body mass space) that bounds all the species within the community.
A list
containing the values
nodes |
The names of the nodes that make up the convex hull. |
points |
A matrix containing columns ‘x’ and ‘y’ that contain the coordinates of the points that make up the convex hull. |
area |
The area within the convex hull. |
Lawrence Hudson
Leaper, R. and Raffaelli, D. (1999) Defining the abundance body-size constraint space: data from a real food web. Ecology Letters 2, 3, 191–199.
data(TL84) # Compute convex hull convex.hull <- NvMConvexHull(TL84) # The nodes that form the hull convex.hull$nodes # The area of the hull convex.hull$area # Plot the hull in red around the nodes PlotNvM(TL84) polygon(convex.hull$points, lwd=2, border='red')