[Rd] is.vector(as.vector(x)) is FALSE

Gabor Grothendieck ggrothendieck at myway.com
Sun Oct 17 17:43:45 CEST 2004


I would have thought it would be an error to attempt and fail.
Actually, to make it a vector all that has to be done is to zap the dim 
attribute:

   dim(x1mat) <- NULL  # now its a vector

It seems to know how to do that in the case of an atomic 
matrix, just not a non-atomic one.  Here it is for an
atomic matrix where it does return TRUE:

   is.vector(as.vector(matrix(1:12,4)))  # TRUE

 <Matthias.Kohl <at> uni-bayreuth.de> writes:

: 
: maybe, the point is that is.vector "attempts to coerce its argument into a
: vector", but here it fails
: 
: is.matrix(as.vector(x1mat))
: [1] TRUE
: 
: Matthias
: 
: >
: > The following, which was recently discussions on the rcom-l list,
: > is a situation where coercing x1mat to a vector using as.vector
: > results in an object that is.vector says is not a vector:
: >
: >      R> x1mat<-matrix(list(1,1.1,1+1i,"a",NA,NaN), 3, 2)
: >      R> is.vector(as.vector(x1mat))
: >      [1] FALSE
: >
: > ______________________________________________
: > R-devel <at> stat.math.ethz.ch mailing list
: > https://stat.ethz.ch/mailman/listinfo/r-devel
: 
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