More Elaborate Plots
The plots described so far were designed for exploring the
distribution of a single variable and the relationship among two
variables. This section describes some plots and techniques that are
useful for exploring the relationship among three or more variables.
The techniques and plots described in the first four subsections are
simple, requiring only simple commands to the listener and mouse
actions. The fifth subsection introduces the concept of a plot
object and the idea of sending messages to an object from the
listener window. These ideas are used to add lines and curves to
scatter plots, and the basic concepts of objects and messages will be
used again in the next section on regression models. The final
subsection shows how Lisp iteration can be used to construct a dynamic
simulation–a plot movie.
Subsections