On 02/03/2014 05:18 PM, Roy Stogner wrote:
>
> On Sat, 1 Feb 2014, Jens Lohne Eftang wrote:
>
>> I used these arguments for 3D elasticity and they seemed to work well
>> also in combination with DirichletBoundary (why does that break 
>> symmetry?)
>
> When you constrain your element matrix and vector (any constraints,
> but including the heterogenous constraints from DirichletBoundary),
> the default argument "asymmetric_constraint_rows=true" causes your
> matrix to be left in an asymmetric state.  The advantage is that in
> this case the linear solver can handle your constraint equations for
> you; the disadvantage is an asymmetric state.
> ---
> Roy

With libmesh 0.9.3-pre, If I do use a DirichletBoundary (with a 
ZeroFunction or ConstFunction), and then after calling system.solve() 
loop over my system matrix entries to check symmetry, my matrix is 
symmetric to machine precision. And also the linear solver would have 
complained about any lack of symmetry (I would assume).

Has this default argument been changed in any later versions of libmesh?

Jens

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