R and matrix with 1 row

Question

is it possible to have a matrix with 1 row only in R?

Here is my code:

   nas <- which(!is.na(y))   
   x <- x[nas,]
   y <- y[nas]

   ...
         


        

Answer 1

You need to specify drop = FALSE to stop R coercing a matrix or array to the lowest possible number of dimensions. See ?`[` for more details.

x <- matrix(1:4,ncol=2)
x[1,]
## [1] 1 2
x[1,,drop=F]
##      [,1] [,2]
## [1,]    1    3