Thanks for your immediate response Mr.Ballarin. I am having dolfinx version 0.7.1, so when I ran with the first correction,
+ mesh._cpp_object, points, 1e-6)
+ cells = np.array(cells, dtype=np.int32)
It shows me the following error, so i dropped the term. Without it I can able to get the value of basis values and cells in my version but while adding this to matrix and solving makes error.
In response to your last statement, I used the values sir, in the class NonlinearPDEproblem, in the thought of adding it to the b matrix. Maybe this approach of adding is wrong, because of the error. So could you please confirm me that, also if it is not the right way, sir please do suggest me some advice of adding the same as this is the only approach I found from the previous topics and discussion. I am sure that from the instruction (How to construct a sparse matrix used for calculating function values at multiple points - #4 by dokken) that I need to use basis values to insert it to matrix/vector but I am lacking how to. Could you please help?
Thank you very much again for your time and considerations. It means a lot.