Re : Re : Mixing tapply and diff

[Tristan Lorino <tristan.lorino@lcpc.fr>]

Message de Tristan Lorino, reçu le jeudi 16 février 2006 à 09:51 :

TL> Message de Dimitris Rizopoulos, reçu le jeudi 16 février 2006 à 09:41 :

DR>> you already have it; you could use:

DR>> vals <- tapply(as.vector(SDF1$V1), SDF1$V2, diff)
DR>> out <- data.frame(id = rep(unique(SDF1$V2), sapply(vals, length)), 
DR>> diff = vals)
DR>> out

vals <- tapply(as.vector(SDF1$V1), SDF1$V2, diff)
out <- data.frame(id = rep(unique(SDF1$V2), sapply(vals, length)), diff = 
unlist(vals))
out

.. with "unlist" works fine...





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