Hi, I'm doing a function that describe two populations in competition. that's the function that i wrote:
exclusao<-function(n10, n20, k1, k2, alfa, beta, t){ n1<-k1-(alfa*n20) n2<-k2-(beta*n10) if(t==0){plot(t, n10, type='b', xlim=range(c(1:t),c (1:t)), ylim=range(n10, n20), xlab='tempo', ylab='tamanho populacional') points(t, n20, type='b', col="red") points(t,n10,type="b", col="black") legend("topleft", c("Pop1","Pop2"), cex=0.8, col=c ("black","red"), pch=21:21, lty=1:1); } if(t>0){ for (i in 1:t){ n1[i==1]<-n1 n2[i==1]<-n2 n1[i+1]<-k1-alfa*n2[i] n2[i+1]<-k2-beta*n1[i] if(n1[i]==0){n1[i:t]==0} if(n2[i]==0){n2[i:t]==0} } plot(c(1:t), n1[1:t], type='b', xlim=range(c(1:t),c (1:t)), ylim=range(n1[1:t], n2[1:t]), xlab='tempo', ylab='tamanho populacional') points(c(1:t), n2[1:t], type='b', col="red") legend("topleft", c("Pop1","Pop2"), cex=0.8, col=c ("black","red"), pch=21:21, lty=1:1); }} Where n10: size population in time 0, n20: size population in time 0, k1: carrying capacity of the population 1, k2: carrying capacity of the population 2, alfa: competition coefficient of population 2 in population 1, beta: competition coefficient of population 1 in population 2, t: time. and when some population becomes 0 (ZERO), i want that population still 0 (ZERO) until the end of "t". i have tried to put " if(n1[i]==0){n1[i:t]==0} if(n2[i]==0){n2[i:t]==0}" after "n2[i+1]<-k2-beta*n1[i]" in the for function, but nothing happens. What may i do ? Thanks Bruno [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.