Breeze-viz is unfortunately rather poorly documented. This can make the learning curve somewhat steep. Fortunately, it is still quite a small project: at the time of writing, there are just ten source files (https://github.com/scalanlp/breeze/tree/master/viz/src/main/scala/breeze/plot). A good way to understand exactly what breeze-viz does is to read the source code. For instance, to see what methods are available on a Plot object, read the source file Plot.scala. If you need functionality beyond that provided by Breeze, consult the documentation for JFreeChart to discover if you can implement what you need by accessing the underlying JFreeChart objects.