[R] Surprise when indexing with a factor.

[Peter Dalgaard]

pallier <pallier at lscp.ehess.fr> writes:

> Given a named vector 'm' and a factor 'f' whose levels match (e.g.
> when 'm' is the result of a 'tapply' command using the factor f as
> INDEX), my intuition is that m[f] means m[as.character(f)]

It's not like we haven't visited this before. As I recall it, the main
argument for the actual behaviour is that otherwise you can *only*
index named vectors with levels a superset of those of the factor.
It makes little sense to have such a restriction, and even less to
have m[f] change if names are added to m.

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
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