Assume that there are five data sets currently read in, all of
them ungrouped initially.
XSPEC> setplot group 1-4 ! The first four data sets are treated as one
group, with the fifth data sets on its own.
Thus all plots will appear to have two
data sets.
XSPEC> setplot group 1 2 3 4 ! The data sets are reset to each be in their
own group.
XSPEC> setplot group 2-3 4-5 ! Now there are three plot groups, being
data set 1, by itself, and data sets 2-3 and
4-5 as groups.
XSPEC> setplot group 1-** ! All the data sets are placed in a single plot
group.