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[Kristian Oelgaard <k.b.oelgaard@xxxxxxxxxx>]

Quoting "Garth N. Wells" <gnw20@xxxxxxxxx>:

> I just tested the new FFC generated code (with quadrature) from the UFL
> input for Poisson. From the input code
>
>      element = FiniteElement("Lagrange", "triangle", 1)
>      v = TestFunction(element)
>      u = TrialFunction(element)
>      f = Function(element)
>
>      a = dot(grad(v), grad(u))*dx(0, {"quadrature_order":1})
>      L = v*f*dx(0, {"quadrature_order":2})
>
> I computed exactly the same solution as with the FFC .form code, but with
>
>      element = FiniteElement("Lagrange", "triangle", 1)
>      v = TestFunction(element)
>      u = TrialFunction(element)
>      f = Function(element)
>
>      a = dot(grad(v), grad(u))*dx
>      L = v*f*dx
>
> I see differences. How is the order of integration being selected?

As far as I remember the UFL algorithm currently just looks at order of the
basis functions:

a: 1*1 = 2
L: 1   = 1

So the difference is expected.

Kristian


> Garth
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