### Form Compiler: uflacs

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2

Hey, I specify 'uflacs' as the form_compiler as follows:

parameters['form_compiler']['representation'] = 'uflacs'

Then I try to run:

V = FunctionSpace(mesh)

f = Function(V)

norm(f, 'L2')

This gives the following WARNING;

FFC: quadrature representation is deprecated! It will ***

*** likely be removed in 2018.1.0 release. Use uflacs ***

*** representation instead.

Could somebody explain how I can enforce form compiler parameters? I have looked up other posts, but could not understand it clearly.

parameters['form_compiler']['representation'] = 'uflacs'

Then I try to run:

V = FunctionSpace(mesh)

f = Function(V)

norm(f, 'L2')

This gives the following WARNING;

FFC: quadrature representation is deprecated! It will ***

*** likely be removed in 2018.1.0 release. Use uflacs ***

*** representation instead.

Could somebody explain how I can enforce form compiler parameters? I have looked up other posts, but could not understand it clearly.

Community: FEniCS Project

### 1 Answer

2

Representation is overloaded just in norm(). Other user calls to assemble(), etc. will use the right representation.

Thanks for reporting the issue, it is now tracked at https://bitbucket.org/fenics-project/dolfin/issues/949 and will be solved before the release.

Thanks for reporting the issue, it is now tracked at https://bitbucket.org/fenics-project/dolfin/issues/949 and will be solved before the release.

1

Yes, the workaround is

But note that this is not very accurate if

` assemble((grad(f-f_ref)**2+(f-f_ref)**2)*dx)`

.But note that this is not very accurate if

`f_ref`

is not a polynomial and can't be integrated exactly be a quadrature formula. There is a degree rise trick which `errornorm()`

uses.` `

written
7 months ago by
Jan Blechta

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f = function(V)

f_ref = function(V_ref)

H1_norm(f - f_ref)

using uflacs form?