When I ran
> test=NULL > for (i in 1:10){ + if (i%%2!=0){ + test=c(test,i) + i=i+2}} > test [1] 1 3 5 7 9
I was expecting the same output as
> test=NULL > i=1 > while (i<11){ + if (i%%2!=0){ + test=c(test,i) + i=i+2} + i=i+1} > test [1] 1 5 9
So this means that the dummy index in R “for” loops cannot be tweaked that easily. I seem to remember doing this kind of (dirty) tricks with earlier versions… Now, Alessandra and Robin think this is a good thing that the for loop is robust against this kind of non-sense, so I may be a minority in complaining about this lack of control [for me, if not for for].