list_of_matrices: Checks that an object is a list of matrices
Description
Checks that an object is a list, and also
that the list is a collection of matrices.
Currently returns FALSE
on an empty list
Usage
list_of_matrices(list_to_check, allow_null = TRUE)
Arguments
list_to_check
The potential list to check
allow_null
If an element is NULL
, is that OK?
Default TRUE