Creating lists from matrices

Hi,

One could use the following:

 >  mm=matrix(letters[1:9],ncol=3,byrow=TRUE)
 >  lapply(apply(mm,1,list),function(el)el[[1]])
[[1]]
[1] "a" "b" "c"

[[2]]
[1] "d" "e" "f"

[[3]]
[1] "g" "h" "i"

You could also have a look at as.data.frame.matrix, which transform a 
matrix into a data.frame efficiently. data.frames are internaly structured 
as lists...

Eric

Hello,

I am using R 1.9.1 on Windows 2000 SP4. I have the following problem:

Say I have a matrix,

my.matrix

       [,1]   [,2]   [,3]
[1,]   "A"   "B"   "C"
[2,]   "D"   "E"   "F"
[3,]   "G"   "H"   "I"

I would like to apply an operation to this matrix which returns a list 
my.list
containing the following 3 elements,

my.list

[[1]]
[1] "A" "B" "C"
[[2]]
[2] "D" "E" "F"
[[3]]
[3] "G" "H" "I"

That is, each row of the original matrix is turned into a vector and these
vectors are collected to a list. How do I do this?

Thanks,
 Alexander

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