Returns the method names used to compute the NMF fits in
the list. It returns
NULL if the list is empty.
`algorithm`(object, string = FALSE, unique = TRUE)
- a logical that indicate whether the names
should be collapsed into a comma-separated string.
- a logical that indicates whether the result
should contain the set of method names, removing
duplicated names. This argument is forced to
- an object computed using some algorithm, or
that describes an algorithm itself.