NDSolve::ntdv NDSolveValue::ntdv ParametricNDSolve::ntdv ParametricNDSolveValue::ntdv
Details
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- This message is generated when NDSolve is unable to solve for the derivatives in a differential equation.
- NDSolve uses Solve to solve symbolically for the derivatives in a differential equation.
- This error will occur if the equations do not have a solution, or if it is not possible to solve for the derivatives by algebraic methods.
- In some cases this error can be handled by solving for the derivatives separately and using those solutions in the input to NDSolve.
- Off[message] switches off the message; On[message] switches it on. For example: Off[NDSolve::ntdv].
Examples
Basic Examples (1)
For differential algebraic equations, NDSolve tries to explicitly solve for the highest-order derivative but may fail due to the time constraint imposed for performing symbolic computations:
The message suggests using Method{"EquationSimplification""Residual"}. This does work, but it does not find all solutions:
Increase the time constraint needed to get an explicit formulation:
Use the "StiffnessSwitching" time-integration method to avoid stiffness issues: