rray_dim_n() computes the dimensionality (i.e. the number of dimensions).




An object.


An integer vector containing the number of dimensions of x.


One point worth mentioning is that rray_dim_n() is very strict. It does not simply call the generic function dim() and then check the length. Rather, it explicitly pulls the attribute for the "dim", and checks the length of that. If an object does not have an attribute, then the dimensionality is 1.

This means that data frames have a dimensionality of 1, even though dim() defines a method for data frames that would imply a dimensionality of 2.


x_1_by_4 <- rray(c(1, 2, 3, 4), c(1, 4)) rray_dim_n(x_1_by_4)
#> [1] 2
# NULL has a dimensionality of 1 rray_dim_n(NULL)
#> [1] 1
# The dimensionality of a data frame is 1 rray_dim_n(data.frame())
#> [1] 1