Help with system of advection–diffusion–reaction equations tutorial problem

Question

Hello,

I am a new FEniCS user. I am trying to simulate the convection advection model given in the tutorial problem.
The code is executing properly however, I am not able to see any plots as the complier is ignoring the interactive() command in the example code.

The problem that it is showing me is:

Reading vector value at t = 5.
No Jacobian form specified for nonlinear variational problem.
Differentiating residual form F to obtain Jacobian J = F'.
Solving nonlinear variational problem.
Newton iteration 0: r (abs) = 2.551e-04 (tol = 1.000e-10) r (rel) = 1.000e+00 (tol = 1.000e-09)
Solving linear system of size 5895 x 5895 (PETSc LU solver, petsc).
Newton iteration 1: r (abs) = 1.677e-14 (tol = 1.000e-10) r (rel) = 6.572e-11 (tol = 1.000e-09)
Newton solver finished in 1 iterations and 1 linear solver iterations.
*** Warning: No plots have been shown yet. Ignoring call to interactive().

Please help in what I should be doing to get the plots.
Thank you.

Regards,
Ratnesh

Comments

Did you call the plot function before interactive?

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Or could it be that VTK hasn't been installed on the system? I'm not sure if interactive() works when matplotlib is the plotting backend.

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Maybe, but if you call interactive() without calling plot first, you get the same warning:

In [1]: from dolfin import *

In [2]: interactive()
*** Warning: No plots have been shown yet. Ignoring call to interactive().

In [3]: 

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Yes I have called plot before interactive() as given in the tadvection–diffusion–reaction tutorial

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How did you install FEniCS?

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I installed FEniCS on ubuntu 16.04 LTS version. I also installed the numpy add-on in python. I am running and writing the codes in python 2.7

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But how did you install FEniCS? Did you use the Ubuntu packages from the FEniCS PPA, the Docker images, or did you install from source?

Does the following code give you a plot?

from dolfin import *
mesh = UnitSquareMesh(16, 16)
plot(mesh)
interactive()

If that works, then please show us a complete minimal example that shows the problem.