A support containing nothing: no atoms and no continuous part.
Details
No distribution has an empty support — probability has to go somewhere —
and distribution() rejects one. It exists so that operations on supports
are closed: restricting a support to a region it does not reach has to
return something, and that something is the empty support. It is also the
identity for taking unions.
Its variable type is "empty", which is a different claim from
"unknown". Empty says there is nowhere to place probability; unknown says
nobody specified where.
See also
is_empty_support() to test for it, discrete(),
continuous(), and mixed() for supports a distribution can actually have.
Other Support:
atoms(),
is_support(),
support(),
support-construction
Examples
empty_support()
#> <support: empty>
is_empty_support(empty_support())
#> [1] TRUE
# It is also what any of the constructors gives when handed nothing.
continuous(numeric(0))
#> <support: empty>
discrete(numeric(0))
#> <support: empty>
mixed()
#> <support: empty>