[R] for loop should check the looping index !!

[Peter Dalgaard]

johan Faux <johanfaux at yahoo.com> writes:

> Hello ,
>    
>   a<-c(1)
>   for(i in 2:length(a))
>       do.something with a[[i]]
>    
>   I get :
>   Error in a[[i]] : subscript out of bounds
>    
>   Am I missing something here?  Doesnt R check the value of i inside "for" and if the condition is not tru, dont do anything ????

Well,

> 2:1
[1] 2 1


The for loop as such has no idea what you're going to do with the
index variable, so will faithfully try to do.something with a[[2]]

-- 
   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
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