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PDE eigenvalue solution and derived quantities


An EigenResults object contains the solution of a PDE eigenvalue problem in a form convenient for plotting and postprocessing.

  • Eigenvector values at the nodes appear in the Eigenvectors property.

  • The eigenvalues appear in the Eigenvalues property.


There are several ways to create an EigenResults object:

  • Solve an eigenvalue problem using the solvepdeeig function. This function returns a PDE eigenvalue solution as an EigenResults object. This is the recommended approach.

  • Solve an eigenvalue problem using the pdeeig function. Then use the createPDEResults function to obtain an EigenResults object from a PDE eigenvalue solution returned by pdeeig. Note that pdeeig is a legacy function. It is not recommended for solving eigenvalue problems.


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This property is read-only.

Finite element mesh, returned as a FEMesh Properties object.

This property is read-only.

Solution eigenvectors, returned as a matrix or 3-D array. The solution is a matrix for scalar eigenvalue problems, and a 3-D array for eigenvalue systems. For details, see Dimensions of Solutions, Gradients, and Fluxes.

Data Types: double

This property is read-only.

Solution eigenvalues, returned as a vector. The vector is in order by the real part of the eigenvalues from smallest to largest.

Data Types: double

Object Functions

interpolateSolutionInterpolate PDE solution to arbitrary points


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Obtain an EigenResults object from solvepdeeig.

Create the geometry for the L-shaped membrane. Apply zero Dirichlet boundary conditions to all edges.

model = createpde;
applyBoundaryCondition(model,'dirichlet', ...
                             'Edge',1:model.Geometry.NumEdges, ...

Specify coefficients c = 1, a = 0, and d = 1.


Create the mesh and solve the eigenvalue problem for eigenvalues from 0 through 100.

ev = [0,100];
results = solvepdeeig(model,ev)
results = 
  EigenResults with properties:

    Eigenvectors: [5669x19 double]
     Eigenvalues: [19x1 double]
            Mesh: [1x1 FEMesh]

Plot the solution for mode 10.


Version History

Introduced in R2016a