Get matrix element through a vector of indices-CodePudding

I'm trying to parse the coordinates of a matrix from a vector to retrieve an element.

Data:

m <- matrix(1:25, ncol = 5)
v <- c(2,3)

I'm basically trying to get the elementm[2,3], in that case the value 12, by parsing the vector as coordinates:

m[v]

but all I get is NA. I have tried m[paste(v, collapse="\",\""], which also did not work.

I know I could use

m[paste(v[1]), paste(v[2])]

but I'm trying to find a more elegant solution.

Any idea how to get this to work?

CodePudding user response：

you can try

> m[matrix(v, 1)]
[1] 12

or just

> m[t(v)]
[1] 12

CodePudding user response：

Few more options:

m[v[1], v[2]]
[1] 12

do.call("[", c(list(m), as.list(v)))
[1] 12

m[v[1]   (v[2]-1) * nrow(m)]
[1] 12