Oh yes, that' exactly what I wanted (in the post-processing case). Thanks. And if I want to do it during integration?
On Friday, September 23, 2016 at 6:21:23 PM UTC+1, Wolfgang Bangerth wrote: > > On 09/23/2016 11:17 AM, dragn...@gmail.com <javascript:> wrote: > > > > Well, the actual situation is more complex, requires a generic solution, > > but it simplifies into a calculation of total quantity through a > > boundary. For instance, a simple case: say we have heat or mass transfer > > problem (or any scalar quantity) and specified some boundary conditions > > (problem-specific), how to get the total heat/mass passing through the > > specified boundary? Theoretically, the equation is something like (c is > > concentration here): > > > > < > https://lh3.googleusercontent.com/-MWUI0byfiww/V-Viw0UincI/AAAAAAAAAAo/Z_b79mL9Rv0kYw9TqBkbn3m_qcBnIKwNwCLcB/s1600/eq200.gif> > > > > > > > > Honestly, I do not understand the theory in the tutorial 44 (it's > > completely out of my area). > > Here is a piece of code that does what you want, though with a bigger > set up to get at the solution gradients and coefficient values than you > probably need: > > > https://github.com/geodynamics/aspect/blob/master/source/postprocess/heat_flux_statistics.cc#L122 > > > It loops over all faces and then over the quadrature points of each face. > > Best > W. > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: bang...@colostate.edu > <javascript:> > www: http://www.math.colostate.edu/~bangerth/ > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to dealii+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
