Let denote a two-dimensional linear interval arithmetic,
such as
or
.
We will not ensure that R represents
directly;
we will instead work with
.
The interval specification
is computed by evaluating the
specification S using the interval arithmetic
.
The interval inclusion property assures us that
Other linear interval arithmetics may be used,
such as or
,
given an appropriate
.
Better renderings may be obtained by taking S
into account when choosing
and
.
Jeff Tupper | March 1996 |