JCCKit is a nice and small library for creating scientific charts and plots. Like PlantUML, it's a very text oriented solution written in Java. The primary goal of PlantUML is to document software, and in some occasions, having charts or plots can be usefull for that goal. So even if PlantUML has not been designed for charts/plots, it was easy to integrate JCCKit. The only change done was the of colors recognized by PlantUML. You will have to refer to the JCCKit User Guide to fully understand the following examples. There is also a PDF document for the configuration.