We have seen how easy it is to create multi-panel plots using xyplot(), barchart() and other functions of lattice. We mentioned in the introduction that lattice graphics can be customized on the fly. Yet, we haven't taken that opportunity yet. In this section, we will see how lattice plots can be customized using the update() function. Note that the customizing can be done when creating the object as well. We will use another simple dataset for this purpose: the ChickWeight dataset. This dataset contains four attributes which describe the growth of chickens through time, with several diets; weight: the weight of the chicken, Time: the age of the chicken, Chick: the identifier of the chicken, and Diet: how the chicken was fed.
Our interest will focus on the relationship between the diet and growth (variations in weight through time).
xyplot(weight ~ Time | Diet, data=ChickWeight)
As can be seen in the figure below, chickens increase in weight through time, with all diets. It...
