Using values of a differential equation to plot a new graph
Im running a basic SIR model for some students (lots of examples of the site). However, that system of differential equations contains 3 equations. I want to use the individual values of the I' curve over time to plot a 4th, different equation and graph altogether. I cannot seem to do this, no matter how I try. Basically, I would need to obtain the numerical value of I' at every time t (a measure of disease prevalence) and apply a modification to that equation.
Any help is appreciated!