Piecewise differential equations

[ChrisRackauckas]

This is discussed here and I haven’t added it to the FAQ yet:

Handling Instability When Solving ODE Problems

Thanks for the example. I will share as little as possible but just a snippet in order to explain what’s going on to others. This is a good teaching opportunity. I was able to find out that the problem is that, in the statement k9*X3/(k10*k11/(k12*(1.-min(1.,k13+k14*X5))) + X3) when X3 and X5 are dual numbers, the value of k11/(k12*(1.-min(1.,k13+k14*X5))) is NaN for the derivative components when the condition makes it the constant 1.0 (since the derivative of the minimum of in the denominat…