R/Hexagons.R

In SOMEnv: SOM Algorithm for the Analysis of Multivariate Environmental Data

#' Function to draw an hexagonal SOM map
#'
#' Draws an hexagonal SOM map using x, y coordinates for the hexagon centers
#'
#' @param Coords matrix containing the x and y coordinates of the hexagon centers
#' @param Row Number of SOM map rows
#' @param Col Number of SOM map columns
#' @param color Filling color of the hexagons (default NA)
#' @param border Border color of the hexagons (default "gray")
#' @param unitcell The distance side to side between two parallel sides of the hexagon (default 1)
#' @author Sabina Licen
#' @return A hexagonal SOM map
#' @importFrom graphics par
#'
#' @references {Licen, S., Cozzutto, S., Barbieri, P. (2020) Aerosol Air Qual. Res., 20 (4), pp. 800-809. DOI: 10.4209/aaqr.2019.08.0414
#' }
#' @export
#' @examples
#' Coord<-CodeCoord(10,5)
#' Hexagons(Coord,10,5)


Hexagons<-function (Coords,Row,Col,color = NA, border = "gray",unitcell=1)
{  Apo<-unitcell/2;R<-Apo/(cos(pi/6));
   plot(c(1-2*Apo,Col+Apo),c(1-R,1+(Row-1)*(R*1.5)+R),
   type="n",xlab="",ylab="",xaxs="i",yaxs="i",xaxt="n",yaxt="n",bty="n");
   for (i in c(1:nrow(Coords))) {Hexa(Coords$X[i],Coords$Y[i],color=color,border=border)}
}