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InterpolatingFunction::femdmval

InterpolatingFunction::femdmval

Details

  • This message is generated when an InterpolatingFunction expression is evaluated outside of its domain.
  • Although this message does not necessarily represent an error, extrapolation beyond the range of interpolation can give unexpected or misleading results.
  • Off[message] switches off the message; On[message] switches it on. For example: Off[InterpolatingFunction::femdmval].

Examples

Basic Examples  (1)

Create a solution to a PDE and evaluate the InterpolatingFunction expression outside the domain for which the solution was found:

Wolfram Language code: ufun = NDSolveValue[{Laplacian[u[x, y], {x, y}] == 1, DirichletCondition[u[x, y] == 0, True]}, u, {x, y}∈Rectangle[]]; ufun[2, 2]

Generally speaking, nothing is known about the solution beyond the boundary conditions. Nevertheless, this behavior can be switched off:

Wolfram Language code: ufun = NDSolveValue[{Laplacian[u[x, y], {x, y}] == 1, DirichletCondition[u[x, y] == 0, True]}, u, {x, y}∈Rectangle[], "ExtrapolationHandler" -> {Automatic, "WarningMessage" -> False}]; ufun[2, 2]

More information can be found in the tech note Finite Element Options for NDSolve.