As a followup, I have attached a screenshot of where the element in the error message is pointing. It is intriguing that the coordinates of all 4 nodes have virtually the same y-axis location (hence the hmin of 10^-11). I have circled the respective edge that these coordinates define.
I should also note that I am using a custom function for flagging elements for refinement/coarsening. I have a scalar function define on the elements, and based on the value of the function I mark them for refinement or coarsening. So, this is a simple less-then/greater-than block. Not sure I am supposed to check for more parameters before flagging. Thanks, Manav > On May 1, 2019, at 5:25 PM, Manav Bhatia <[email protected]> wrote: > > Hi, > > I am using h-refinement in my analysis, which uses the mesh function > routines to compute the value of the function in the interior of an element. > > All of my elements in the original mesh (before any refinements) are > squares (quad4). > > For the most part everything works out fine without any issues. > Occasionally, however, I will get an error in the inverse_map() like this. I > am particularly perplexed by the hmin() size of 10^-11. > > The size of my elements before refinement is hmin() = .015 and I allow a > max of 4 refinements in any element. Would there be any reason to expect an > hmin of order 10^-11 in this case? > > Thanks, > Manav > > > WARNING: At least one element took more than 10 iterations to converge in > inverse_map()... > Rerun in devel/dbg mode for more details. > ERROR: Newton scheme FAILED to converge in 21 iterations in element 16514 for > physical point = (x,y,z)=( 0.27, 0.2775, 0) > Elem Information > id()=16514, processor_id()=2 > type()=QUAD4 > dim()=2 > n_nodes()=4 > 0 Node id()=13234, processor_id()=4294967295, Point=(x,y,z)=( 0.27, > 0.2775, 0) > DoFs= > 1 Node id()=604, processor_id()=2, Point=(x,y,z)=(0.271875, 0.2775, > 0) > DoFs=(0/0/13470) (0/1/13471) (0/2/13472) (0/3/13473) (0/4/13474) > (0/5/13475) (2/0/2245) (3/0/2245) > 2 Node id()=13235, processor_id()=4294967295, Point=(x,y,z)=(0.271875, > 0.2775, 0) > DoFs= > 3 Node id()=13233, processor_id()=4294967295, Point=(x,y,z)=( 0.27, > 0.2775, 0) > DoFs= > n_sides()=4 > neighbor(0)=nullptr > neighbor(1)=nullptr > neighbor(2)=nullptr > neighbor(3)=nullptr > hmin()=9.89829e-11, hmax()=0.001875 > volume()=1.85593e-13 > active()=1, ancestor()=0, subactive()=0, has_children()=0 > parent()=672 > level()=4, p_level()=0 > refinement_flag()=DO_NOTHING > p_refinement_flag()=DO_NOTHING > DoFs= > Exiting... > [2] src/fe/fe_map.C, line 1905, compiled Apr 20 2019 at 20:02:41 > _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
