Finite Element Preconditioning on Spectral Element Discretizations for Coupled Elliptic Equations

Figure 4

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

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