search for: occurcence

Hi, Is the ordering of the values returned something on what I can rely on, a form of a standard, that a function called unique in R (in futher versions) will return the uniq elements in order of they first occurcence. > x<-c(2,2,1,2) > unique(x) [1] 2 1 Its seems not to be the standard. E.g. matlab >> x=[2,2,1,2] x = 2 2 1 2 >> unique(x) ans = 1 2 I just noted it because, the way how it is working now is extremely usefull for some applications (e.g tree tra...