ToolPythonIntermediate Poisson's equation with scipy.sparse: two plates in a grounded box I = sp.eye_array(N)
ToolPythonIntermediate Sparse eigenvalues with scipy.sparse.linalg.eigsh: the tones of a drum D2, I = second_difference(n, h), sp.eye_array(n)D2, I = second_difference(N, h), sp.eye_array(N)