Thanks for clearing it up. Then I guess we just solve for u' a(u',v) + a(u0,v) = f(v)
and attach assemblies a(u',v), a(u0,v), and f(v) as usual, then restore u by u = u' + u0. K. Lee. On Fri, Jan 25, 2013 at 12:17 PM, David Knezevic <[email protected] > wrote: > Hi K, > > heterogeneously_constrain_element_matrix_and_vector is not relevant to > Reduced Basis stuff. For Reduced Basis formulations, you have to > transform the problem using a lifting function so that it has zero > Dirichlet BC's --- this is essential since you want your Reduced Basis > space to be a vector space, i.e. it must contain 0 (which would be not > be the case with non-zero Dirichlet BCs). This lifting function approach > is what you described in your email already, so that's fine. > > Once you've transformed your problem using a lifting function, then you > just proceed as normal, e.g. as in reduced_basis_ex1. The only trick is > you have to add your lifting function back on at the end to recover u > from u'. > > David > > > > On 01/24/2013 11:10 PM, Kyunghoon Lee wrote: > > Hi all, > > > > In my previous email regarding inhomogeneous Dirichlet boundary > conditions, > > David suggested using heterogenously_constrain_element_matrix_and_vector > in > > introduction_ex4, but I'm not sure of how to deal with inhomogeneous > > Dirichlet BCs in connection with reduced basis models. Suppose we have a > > simple steady state heat conduction model whose BCs are u = T on \Gamma > and > > u = 0 on the rest surfaces. After variable change, we solve > > > > a(u',v) = f(v) - a(u0,v) > > > > where 1) u' = u - T on \Gamma and u' = u on the rest surfaces; and 2) u0 > = > > T on \Gamma and u0 = zero on the rest surfaces. I thought we build the > LHS > > then call attach_F_assembly to attach it, but in that case, I'm not sure > > how heterogenously_constrain_element_matrix_and_vector can be used. Or > > should we attach a(u',v) and f(v) as usual then call > > heterogenously_constrain_element_matrix_and_vector to impose - a(u0,v) on > > the LHS? I'd appreciate if someone can briefly describe how the function > > work. > > > > Regards, > > K. Lee. > > > ------------------------------------------------------------------------------ > > Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, > > MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current > > with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft > > MVPs and experts. ON SALE this month only -- learn more at: > > http://p.sf.net/sfu/learnnow-d2d > > _______________________________________________ > > Libmesh-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/libmesh-users > > > > ------------------------------------------------------------------------------ > Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, > MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current > with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft > MVPs and experts. ON SALE this month only -- learn more at: > http://p.sf.net/sfu/learnnow-d2d > _______________________________________________ > Libmesh-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/libmesh-users > ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. ON SALE this month only -- learn more at: http://p.sf.net/sfu/learnnow-d2d _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
