Finite Element Preconditioning on Spectral Element Discretizations for Coupled Elliptic Equations

Figure 3

The eigenvalues of 𝖡_ℎ2⁻¹𝖠_𝑁2 for 𝐸=4,6,8,10 and 𝑁=4 when 𝛿=1,𝐛=[1,1]^𝑇.

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