build {starm}

Creation of the neighbourhood's matrix.

Description

Creation of the neighbourhood's matrix.

Usage

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.

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.

Value

The neighborhood matrix

Note

If returnplot = TRUE, variable$plot will return an exemple of the choosen neighborhood on a center point of the dataset.

Examples

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")