Hi, I would like to convert a numeric differential-algebraic equation to a symbolic model using modelingtoolkitize. However, when then trying to convert it back to an ODEProblem, I get an overdetermined warning and when trying to solve it an InitialFailue. The overdetermined warning is expected sinc…

You can do this by setting the initial condition to nothing: prob2 = ODEProblem(sys, [:u2 => nothing], tspan) After which the problem solves without problems: sol2 = solve(prob2) # yay! plot(sol2, idxs = [:u1, :u2]) For reference, there is a page on the ModelingToolkit docs about system initiali…

Overdetermined system when using modelingtoolkitize

Specific Domains Modelling & Simulations

jessehummel October 15, 2025, 4:00pm 3

That works and thank you for the link!

1 Like

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Overdetermined system when using modelingtoolkitize

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