How do I fix tensor integration?

General
1

Here the D=D(x,y) is a variable diffusion coefficient. I have tried both inner product and dot product but getting the same problem. Can some help me with a suggestion to fix this problem?

Can only integrate scalar expressions. The integrand is a tensor expression with value shape (5,) and free indices with labels ().
Traceback (most recent call last):
File “SEIRD_var.py”, line 137, in
beta_e / n * s * e, vs) * dx + D*dot(n * grad(s), grad(vs)) * dx
File “/usr/local/lib/python3.6/dist-packages/ufl/measure.py”, line 420, in rmul
(integrand.ufl_shape, integrand.ufl_free_indices))
File “/usr/local/lib/python3.6/dist-packages/ufl/log.py”, line 172, in error
raise self._exception_type(self._format_raw(*message))
ufl.log.UFLException: Can only integrate scalar expressions. The integrand is a tensor expression with value shape (5,) and free indices with labels ().

2

You can integrate only scalar, I think. If you want integrate a tensor, you need integrate each coordinate.

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