A is not a matrix. I presume you meant B. If so:
> B[!C] <- 0
> B
[,1] [,2] [,3] [,4]
[1,] 1 6 0 0
[2,] 2 0 0 0
[3,] 3 0 0 0
[4,] 4 0 0 19
[5,] 5 0 0 0
Cheers,
Bert
On Sat, Sep 5, 2020 at 11:18 AM Vivek Sutradhara <[email protected]>
wrote:
> Hi
> I would like to get help in combining two matrices. Here is my example:
> A <- 1:20
> B <- matrix(A,nrow=5,ncol=4)
> # B is a numerical matrix
> C <- B<7
> C[4,4] <- TRUE
> # C is a logical matrix
> # if I combine A and C, I get a vector
> D1 <- A[C==TRUE]
> D1
> D2 <- A[C==FALSE]
> D2
>
> I want to get a matrix with the same dimensions as matrix A. At the
> coordinates given by the vector D1, I want to retain the values in
> matrix A. At the locations in D2, I want a zero value.
> I want to know if I can do this without using any loops.
> Thanks, Vivek
>
> [[alternative HTML version deleted]]
>
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> and provide commented, minimal, self-contained, reproducible code.
>
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______________________________________________
[email protected] mailing list -- To UNSUBSCRIBE and more, see
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
