[R] Why does a[which(b == c[d])] not work?

[Martin Maechler]

Your question has been answered by Achim and Peter Dalgaard (at least).

Just a note:

Using  
       a[which(logic)] 
looks like a clumsy and inefficient way of writing
       a[ logic ]

and I think you shouldn't propagate its use ...

Martin Maechler <maechler at stat.math.ethz.ch>	http://stat.ethz.ch/~maechler/
Seminar fuer Statistik, ETH-Zentrum  LEO C16	Leonhardstr. 27
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