This note provides simplification results concerning frequency domain
properties of systems containing an interval plant. The problem is for
mulated in a general enough manner to encompass most problems involvin
g one interval plant. It is shown that under rather mild assumptions,
all the key information can be obtained using just 32 one-dimensional
subsets of the interval plant called the 32 segments. For the general
problem, it is not possible to avoid dealing with the segments. Howeve
r, for the special yet important case of computing open-loop Bode plot
s, this note shows that eight subpolynomials of the interval plant are
sufficient.