I don’t get why this doesn’t work: @variables t z[1:2,1:2](t) z = collect(z) Dt = Differential(t) eqs = Dt.(Dt.(z[:])) .~ 1 u0 = vcat(z[:] .=> 0., Dt.(z[:]) .=> 1.0) tspan = (0.0, 10.0) @named sys = ODESystem(eqs) prob = ODEProblem(sys, u0, tspan) The error message is ERROR: ArgumentError: A d…

ModelingToolkit, initial data for second order ODE with state vector

ChrisRackauckas September 29, 2021, 10:10am 2

It looks like a missing heuristic on array variables. Worth an issue.

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