
126 Chapter 4 Interval arithmetic
used in Figure 4.3 indicates the inequality (4.6.8). All interval structures, the opera-
tions of which are executable on a computer, are underlined in Figure 4.3.
4.7 Complex interval arithmetic
To complete our discussion of all spaces displayed in Figure 1, it remains to consider
the complex interval spaces, which we now proceed to do.
Let fR, N , C, , =, g be a completely and linearly ordered division ringoid with the
neutral elements o and e,andletCR :Df.x, y/ j x, y 2 Rg be the set of pairs over R.
If in CR we define equality, the order relation , and the operations ı2fC, , , =g by
means of the usual formul ...