Segue o script e os dados em anexo.
event=Caso22
x <- c(0,6,6,0)
y <- c(0,0,8,8)
poly=cbind(x,y)
s=seq(1,5,1)
tm=seq(1,5,1)
anaksenv<-function(event, poly, s, tm, nsim = 10){
#
# This function implements monte-carlo simulations
# to create and plot simulation envelopes to test
# against the hypothesis of complete temporal randomness (CTR)
# of an observed spatial-temporal point pattern.
# It uses the spatial k-function and the cramer-vonMises measure of distance.
#
# OBS: You need splancs loaded
#
# Where:
# - event: A 3xn matrix that contains the coordinates and times of the events
# - poly: A polygon enclosing the points
# - s: A vector of spatial distances for the analysis.
# - tm: A vector of times for the analysis
# - nsim: Number of monte-carlo simulations
#
#
library(splancs)
#
# Starting values
#
x<-event[,1]
y<-event[,2]
t<-event[,3]
maxx<-max(x)
maxy<-max(y)
minx<-min(x)
miny<-min(y)
lent<-length(x)
pontos<-cbind(x,y)
tl<-cbind(min(t),max(t))
#
# Get the K-function for space and time of the observed point pattern
#
ksto <- stkhat(pts=pontos, times=t, poly=poly, tlimits=tl, s=s, tm=tm)
ko <- ksto$ks
#
# Doing Monte-Carlo simulation under the CSR
#
hold<-matrix(0,nsim,length(s))
for(i in (1:nsim)) {
tt<-floor(runif(lent,min(t),max(t)))
xx<-floor(runif(lent,minx,maxx))
yy<-floor(runif(lent,miny,maxy))
pont<-cbind(xx,yy)
tll<-cbind(min(tt),max(tt))
kstmc<-stkhat(pts=pont, times=tt, poly=poly, tlimits=tll, s=s, tm=tm)
kko<-kstmc$ks
hold[i,]<-kko
}
#
up<- apply(hold,2,max)
dow<- apply(hold,2,min)
#
# Creating plot
#
par(pty = "s")
plot(s, up, type = "n", xlab = "Distância", ylab = "Função K espacial")
lines(s, ko, col="blue")
lines(s, up, lty=2, col="red")
lines(s, dow,lty=2,col="red")
}
Desde já muito obrigada!!