R/encloseVarBoundaries.R

In cb-agr/agriPlot: agriPlot - Practical geospatial tools for agricultural field research planning and basic analysis

# req lib: library(rgeos)
#encloseVarBoundaries.R takes fieldBookLLSPDF as input and through a series of functions generates blocks from a user-specific blocking input through a minimumb bounding geometry convex hull algorithm implemented in regeos. 

encloseVarBoundaries <- function(fieldBookLLSPDF,blocking){
fieldBookLLSPDF <- fieldBookLLSPDF
myBlocks <- blocking
fieldBookLLSPDFSplit <- base::split.data.frame(fieldBookLLSPDF,fieldBookLLSPDF[[myBlocks]], drop=FALSE)
fieldBookLLSPDFChull <- lapply(fieldBookLLSPDFSplit, function(x){rgeos::gConvexHull(x)}) 
fieldBookLLSPDFChull <- mapply(fieldBookLLSPDFChull, names(fieldBookLLSPDFChull), SIMPLIFY = FALSE,
                               FUN = function(x,y){x@polygons[[1]]@ID <- y
                               return(x)})
fieldBookLLSPDFChull <- do.call(rbind,fieldBookLLSPDFChull)
fbToChullSPDF <- SpatialPolygonsDataFrame(fieldBookLLSPDFChull, data.frame(blocks = names(fieldBookLLSPDFChull)),match.ID = FALSE)
return(fbToChullSPDF)
}