Explore computational methods for simulating and analyzing ecological systems in this 42-minute lecture from the Serrapilheira/ICTP-SAIFR Training Program in Quantitative Ecology. Delivered by Renato Coutinho from UFABC, the fourth class covers essential topics such as plotting techniques, legend creation, and various plot types. Delve into exercises from the previous day, addressing floating point issues and order of operations. Learn about the Fibonacci sequence and its implementation, along with testing methodologies. Investigate power calculations, including negative powers, and gain insights into effective computational approaches for ecological research.