sHexDist is supposed to calculate euclidian distances between
each pair of hexagons/rectangles in a 2D grid of input "sTopol" or
"sMap" object. It returns a symmetric matrix containing pairwise
dist: a symmetric matrix of nHex x nHex, containing pairwise distances, where nHex is the total number of hexagons/rectanges in the grid
The return matrix has rows/columns ordered in the same order as the "coord" matrix of the input object does.
# 1) generate an iid normal random matrix of 100x10 data <- matrix( rnorm(100*10,mean=0,sd=1), nrow=100, ncol=10) # 2) from this input matrix, determine nHex=5*sqrt(nrow(data))=50, # but it returns nHex=61, via "sHexGrid(nHex=50)", to make sure a supra-hexagonal grid sTopol <- sTopology(data=data, lattice="hexa", shape="suprahex") # 3) initialise the codebook matrix using "uniform" method sI <- sInitial(data=data, sTopol=sTopol, init="uniform") # 4) calculate distances between hexagons/rectangles in a 2D grid based on different objects # 4a) based on an object of class "sTopol" dist <- sHexDist(sObj=sTopol) # 4b) based on an object of class "sMap" dist <- sHexDist(sObj=sI)