Fem.petsc not found in complex-mode

dolfinx
1

Dear FEniCS community.

I’m facing an AttributeError error when trying to run a code with complex-mode in Dolfinx v0.7.3 Docker image. The code below

import dolfinx
import ufl
import basix
from mpi4py import MPI


msh = dolfinx.mesh.create_interval(comm=MPI.COMM_WORLD,
                                   nx=10, points=[-1, 1])


Ph = basix.ufl.element("Lagrange", msh.basix_cell(), 1)

V = dolfinx.fem.functionspace(msh, Ph)
u = ufl.TrialFunction(V)
v = ufl.TestFunction(V)

K = -ufl.inner(ufl.grad(u), ufl.grad(v)) * ufl.dx
Kform = dolfinx.fem.form(K)

dolfinx.fem.petsc.assemble_matrix(Kform, bcs=[])

is followed by the error

AttributeError: module 'dolfinx.fem' has no attribute 'petsc'

This code runs ok if we use real-mode. I cannot reproduce this on the dolfinx conda installation.

Thanks in advance!

2

You should explicitly import the petsc sub-module,
ie
import dolfinx.fem.petsc.
This is because petsc is not a mandatory requirement.

3

Im still getting this error
AttributeError: module ‘dolfinx’ has no attribute ‘has_petsc’

4

We can’t be of much more help unless you tell us how you installed dolfinx.

5

Do I need to install C++ core before pip install. If yes could you please elaborate on it as the instructions on the website are not descriptive enough for me. Apologies for my ignorance

6

You may want to follow one of the ways described in GitHub - FEniCS/dolfinx: Next generation FEniCS problem solving environment . If you are new to dolfinx, I would suggest using a binary installation.

This thread is going off-topic from the original message. I am going to close this, and if you have further installation questions you can open a new topic.