transform a matrix wtih 2 columns into a multimap

Posted by Derek on Stack Overflow See other posts from Stack Overflow or by Derek
Published on 2010-03-19T14:59:19Z Indexed on 2010/03/19 15:01 UTC
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multimap

Hi,

I am wondering if there is a way to transform a matrix of 2 column into a multimap or list of list.

The first column of the matrix is an id (with possibly duplicated entries) and the 2nd column is some value.

For example, if I have to following matrix

m<-matrix(c(1,2,1,3,2,4), c(3,2))

i would like to transform it into the following list

[[1]]
3,4
[[2]]
2

Thanks,

Derek

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Developer IT

transform a matrix wtih 2 columns into a multimap - Developer IT

transform a matrix wtih 2 columns into a multimap

r

list

array

multimap

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Update a list from another list

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