[R] R idiom list? [was: Matrix transformation problem

Dietrich Trenkler Dietrich.Trenkler at uni-osnabrueck.de
Wed Jun 11 12:35:41 CEST 2008

Dimitris Rizopoulos schrieb:
> sorry, my previous answer was not correct; you need:
> x <- matrix(c(1,0,0, 0,0,1, 0,1,0, 0,0,1, 0,1,0, 1,0,0),
>    ncol = 3, byrow = TRUE)
> which(t(x == 1), arr.ind = TRUE)[, "row", drop = FALSE]
Dear helpeRs,

I would like to use this thread for a proposal which lingered in my head
for quite a while.  Several years ago I was an APL aficionado and I very
much liked the idea of an APL idiom list (see e.g

Looking at the solution of Dimitris Rizopoulos wouldn't it be nice not to
have it disappear in the archives?  To be explicit I would like to
propose an R idiom list.  If there does exist one please forgive my 

Best regards


Dietrich Trenkler c/o Universitaet Osnabrueck 
Rolandstr. 8; D-49069 Osnabrueck, Germany    
email: Dietrich.Trenkler at Uni-Osnabrueck.de

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