The interval extension 
of the m-ary g
is also defined in two parts:
. The demotions
and 
gracefully handle
undefined domains. When 
is undefined,
and
may take on any value.
The second part,
.
The demotions
and 
demote arbitrary
functions, which map parameters to booleans (defined/undefined),
to functions which are of the form permitted by 
.
The mapping from parameters to booleans is done in two stages:
first, the parameters are mapped to extended reals and then those extended reals
are mapped to booleans, via 
.
The downward
demotion must preserve domain classifications:
demotion operator is a valid demotion operator.
The upward demotion must also preserve domain classifications:
demotion operator is a valid demotion operator.
| Jeff Tupper | March 1996 |