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Problems with plotting

0 votes

Hi, I am testing out Fenics, and when I run the example ft05_poisson_nonlinear.py

however I get:

Calling FFC just-in-time (JIT) compiler, this may take some time.
Solving nonlinear variational problem.
Newton iteration 0: r (abs) = 4.533e+01 (tol = 1.000e-10) r (rel) = 1.000e+00 (tol = 1.000e-09)
Newton iteration 1: r (abs) = 2.614e+01 (tol = 1.000e-10) r (rel) = 5.767e-01 (tol = 1.000e-09)
Newton iteration 2: r (abs) = 7.883e+01 (tol = 1.000e-10) r (rel) = 1.739e+00 (tol = 1.000e-09)
Newton iteration 3: r (abs) = 2.293e+01 (tol = 1.000e-10) r (rel) = 5.058e-01 (tol = 1.000e-09)
Newton iteration 4: r (abs) = 4.990e+00 (tol = 1.000e-10) r (rel) = 1.101e-01 (tol = 1.000e-09)
Newton iteration 5: r (abs) = 3.970e-01 (tol = 1.000e-10) r (rel) = 8.758e-03 (tol = 1.000e-09)
Newton iteration 6: r (abs) = 2.964e-03 (tol = 1.000e-10) r (rel) = 6.539e-05 (tol = 1.000e-09)
Newton iteration 7: r (abs) = 1.272e-07 (tol = 1.000e-10) r (rel) = 2.806e-09 (tol = 1.000e-09)
Newton iteration 8: r (abs) = 1.572e-15 (tol = 1.000e-10) r (rel) = 3.468e-17 (tol = 1.000e-09)
Newton solver finished in 8 iterations and 8 linear solver iterations.
*** Warning: Plotting backend set to 'none'. Plotting disabled.

asked Jul 7, 2017 by SergioM FEniCS Novice (150 points)

Try to set parameters["plotting_backend"] to something, e.g "vtk" or "matplotlib" depending on what is available.

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