How to append specific indices of a matrix in R -

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if have matrix:

x <- matrix(c(0), ncol=2, nrow=2)

x      [,1] [,2] [1,]    0    0 [2,]    0    0

and want change x[,2][2] 1 instead of 0 , save in new matrix y output be:

y      [,1] [,2] [1,]    0    0 [2,]    0    1

how do in r?

if don't want modify original matrix, reverse order of operations want perform, meaning first store copy of matrix x in new variable y , manipulate entries of matrix y.

y <- x y[2,2] <- 1

else, if want change x , afterwards store copy of modified matrix in y... well, guess changes rather obvious: x[2,2] <-1 followed y <- x.


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