This example runs a cosmological simulation using 32^3 particles with the gas density set to the mean baryonic density and no fluctuations (i.e. sigma_8 == 0). The simulation is run without gravity to prevent any numerical fluctuation from growing. The gas is cooling/heating via its interaction with the UV background set by the cooling model. In practice, the gas will follow the equilibirum temperature of the model at all z and only be affected by reionization. Assuming primoridal abundance, the temperature of the gas at different redshifts can be compared to temperatures inferred from observations of the Lyman-alpha forrest. The plotting script runs this comparison once the simulation has completed. Within the EAGLE cooling model, interesting changes are to switch on/off the Helium II reionisation (or change its redshift) as well as the position and amount of energy injected by Hydrogen reionisation. The parameters given the YAML file are the ones used for actual EAGLE galaxy formation runs.