# Creation of the neighbourhood's matrix. ```r build(data = 0, vx = 3, vy = 3, dx = 1, dy = 1, selec = FALSE, t = 0, norm = "euclidean", returnplot = FALSE) ``` ## Arguments - `data`: dataset with first column the X-coordinates of the sites and the second the Y-coodinates of the sites. - `vx`: integer, first parameter of the neighbourhood ( i.e. first parameter of ellipse if `norm = "euclidean"` for instance). `vx = 3` by default. - `vy`: integer, second parameter of the neighbourhood ( i.e. second parameter of ellipse if `norm = "euclidean"` for instance). `vy = 3` by default. - `dx`: positive real, distance between sites on a row. `dx = 1` by default. - `dy`: positive real, distance between sites on a column. `dy = 1` by default. - `selec`: see `t`. - `t`: double. If `selec = TRUE`, each neighborhood will contain only elements which the type is in `t` (see `examples`). - `norm`: Response type : "euclidean" "inf" "abs" "lin". `norm = "euclidean"` by default. - `returnplot`: If `TRUE`, will return the plot of the most recent neighborhhod in addition to the neighborhood matrix. ## Returns The neighborhood matrix ## Details The function will return the neighborhood matrix of a dataset which must contain coodinates in the two first columns and a third column at least with the "type" of each site (it can be only "0" or "1" for example). The parameter `norm` let you choose between 4 sorts of neighborhood : 3 ellipses in norm 1, 2 or infinite (resp "abs","euclidean" and "inf") with the parameters `vx` and `vy` which are the width and the height of the ellipse, and the norm `lin` will condider only sites on the same row and column with the same parameters `vx` and `vy`. ## Note If `returnplot = TRUE`, `variable$plot` will return an exemple of the choosen neighborhood on a center point of the dataset. ## Examples ```r data <- plantillness v <- which((data$NRang <= 20)) data <- data[v,] v <- which(data$NCep <= 20) data<-data[v,] res <- build(data = data) #Example with the plantillness dataset and the plot available : res <- build(data = plantillness,returnplot = TRUE,vx = 5,vy = 5) #Example with the plantillness dataset, only considering the sites of the type "0" : res <- build(data = plantillness, selec = TRUE, t = c(0),vx = 5,vy = 7,norm = "inf") ```

build function