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1D, ODE involving lagrange multiplier and "Failed to evaluate variable Jacobian"
Posted 2011/06/02 15:36 GMT-4 Parameters, Variables, & Functions, Studies & Solvers Version 4.1 0 Replies
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For 2D case, I can define boundary probe and used that in my ODE (global equations), however for 1D problem there are no boundary probes. I see two choices, either to define a point probe that snaps to closest point and get my p_lm/dl.rho there (flux), or to simply define model variable (flux2) for my boundary point as p_lm/dl.rho . However when I try to use either of them in ODE (with an expression for cumulative flux `cflux` like `flux-cfluxt`), I get "Failed to evaluate variable Jacobian" for mod1.p_lm if I used `flux` and for mod1.flux2 if I tried to use defined variable for my boundary point.
What would be the correct way to integrate lagrange multiplier (for prescribed point BC) over time in 1D?
Hello Mikhail Titov
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