9     def __init__(self, da, lambda_):  argument
10         assert da.getDim() == 2
11         self.da = da
16         da = self.da.fortran
18         ierr = Bratu2D.FormInitGuess(da, vec_X, self.lambda_)
23         da = self.da.fortran
26         ierr = Bratu2D.FormFunction(da, vec_X, vec_F, self.lambda_)
31         da = self.da.fortran
34         ierr = Bratu2D.FormJacobian(da, vec_X, mat_P, self.lambda_)
46 da = PETSc.DA().create([N, N], stencil_width=1)  variable
47 app = App(da, lambda_)
50 F = da.createGlobalVec()
52 J = da.createMat()
57 X = da.createGlobalVec()
61 U = da.createNaturalVec()
62 da.globalToNatural(X, U)
64 def plot(da, U):  argument
65     comm = da.getComm()
71         solution = solution.reshape(da.sizes, order='f').copy()
83 if do_plot: plot(da, U)
90 da.destroy()