diag() has a bug (PR#13702)

Full_Name: Michael Spiegel
Version: 2.9.0
OS: linux
Submission from: (NULL) (204.111.252.142)


The diag() function appears to reject the first argument when it is a matrix,
and nrow and ncol arguments are also provided.

foo <- matrix(c(1:4),2,2)
foo

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

diag(foo)

[1] 1 4

diag(foo, 2, 2)

Error in diag(foo, 2, 2) : first argument is array, but not matrix.

is.matrix(foo)

[1] TRUE