NDEigensystem

NDEigensystem[ℒ[u[x,y,…]],u,{x,y,…}∈Ω,n] gives the n smallest magnitude eigenvalues and eigenfunctions for the linear differential operator ℒ over the region Ω.

NDEigensystem[{ℒ1[u[x,y,…],v[x,y,…],…],ℒ2[u[x,y,…],v[x,y,…],…],…},{u,v,…},{x,y,…}∈Ω,n]  gives eigenvalues and eigenfunctions for the coupled differential operators {op1,op2,…} over the region Ω.

NDEigensystem[eqns,{u,…},t,{x,y,…}∈Ω,n] gives the eigenvalues and eigenfunctions in the spatial variables {x,y,…} for solutions u,… of the coupled time-dependent differential equations eqns.

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