teselado

Realizar teselas a partir de os puntos interiores al poligono (convex hull)

library(readxl)
library(deldir)

## deldir 0.1-29

## 
##      Please note that the arguments "col" and 
##      "lty" of plot.deldir() have had their 
##      names changed to "cmpnt_col" and "cmpnt_lty" 
##      respectively, basically to allow "col" and 
##      and "lty" to be passed as "..." arguments. 
##      Also the "plotit" argument of deldir() has 
##      been changed to (simply) "plot". 
##      See the help for plot.deldir() and deldir().

library(geometry)
library(alphahull)
BD_MODELADO <-read_excel("C:\\Users\\yarvis\\Music\\Modelos\\BD_MODELADO.xlsx")

dforiginal <- data.frame(BD_MODELADO)
df<-data.frame(BD_MODELADO) 
df$Avg_X_MCB<-(df$Avg_X_MCB/mean(df$Avg_X_MCB))-0.2
df$Avg_Y_MCE<-(df$Avg_Y_MCE/mean(df$Avg_Y_MCE))-0.2
xy <- matrix(data=c(df$Avg_X_MCB,df$Avg_Y_MCE), ncol=2)

Coordenadas

plot(df$Avg_X_MCB,df$Avg_Y_MCE,pch=19,cex=1)

Teselacion Voronoi

t<- deldir(df$Avg_X_MCB,df$Avg_Y_MCE, sort=T, plotit = T,digits = 4)

## 
##      PLEASE NOTE:  The components "delsgs" and "summary" of the
##  object returned by deldir() are now DATA FRAMES rather than
##  matrices (as they were prior to release 0.0-18).
##  See help("deldir").
##  
##      PLEASE NOTE: The process that deldir() uses for determining
##  duplicated points has changed from that used in version
##  0.0-9 of this package (and previously). See help("deldir").

l<- tile.list(t)
plot(t)

length(t$summary$del.area)

## [1] 313

sum(t$summary$del.area)

## [1] 0

Teselacion Convex Hull Grafica teselas

xy <- matrix(data = c(df$Avg_X_MCB,df$Avg_Y_MCE), ncol = 2)
tch <- delaunayn(xy)
trimesh(tch,xy)

tch1 <- delaunayn(xy, output.options = "Fa")
hist(tch1$areas)

sum(tch1$areas)

## [1] 3.275718e-07

chull <- ahull(xy, alpha = 0.2)
plot(chull, do.shape = TRUE, wlines = "both", col = c(6,4,1,2,3))

Datos modificados

chull <- ahull(xy, alpha = 0.2)
plot(chull, do.shape = TRUE, wlines = "both",
col= c(6,4,1,2,3))

x <- matrix(runif(100), nc = 2)
# Value of alpha
alpha <- 0.2

ahull.obj <- ahull(x, alpha = alpha)

plot(ahull.obj, do.shape = TRUE, wlines = "both", col = c(6, 4, 1, 2, 3))