[Rd] 0/1 vector for indexing leads to funny behaviour (PR#8389)

From: <rasche_at_molgen.mpg.de>
Date: Tue 13 Dec 2005 - 15:05:15 GMT


Full_Name: Axel Rasche
Version: 2.2.0
OS: Linux
Submission from: (NULL) (141.14.21.81)

Dear Debuggers,

This is not a serious problem. Are 0/1 vectors intended to be used as index vectors? If yes, there is a bug. If not, it leads just to some funny behaviour rather than an error message.

In the appendix is some simple code to reproduce the problem. A logical vector as.logic(a) helps by indexing the vector b. The 0/1 vector a just returns the first value "a". But as many times as there is a 1 in a.

Best regards,
Axel

Appendix:

b = c("a","b","c","d")
a = c(0,1,1,0)
b[as.logical(a)]
b[a]
a = c(1,0,1,0)
b[as.logical(a)]

b[a]
a = c(0,1,1,1)
b[as.logical(a)]
b[a]



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https://stat.ethz.ch/mailman/listinfo/r-devel Received on Wed Dec 14 03:17:19 2005

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