Hello,
I'm looking at a time-dependent 1D 'Coefficient Form PDE' problem. I mesh the line with 4 element (5 nodes). So I have 5 degrees of freedom, the relevant system matrices are also 5x5. Also to keep things simple, my shape function is linear.
However, when I use mphgetu(model), I get 7 values, among which only the 1,3,4,5,7th value correspond to u on the nodes. I guess the 2nd and the 6th value has something to do with the boundary? How exactly are they calculated?
Another question: How to get the Lagrange multiplier from mphmatrix?
Many thanks!
I'm looking at a time-dependent 1D 'Coefficient Form PDE' problem. I mesh the line with 4 element (5 nodes). So I have 5 degrees of freedom, the relevant system matrices are also 5x5. Also to keep things simple, my shape function is linear.
However, when I use mphgetu(model), I get 7 values, among which only the 1,3,4,5,7th value correspond to u on the nodes. I guess the 2nd and the 6th value has something to do with the boundary? How exactly are they calculated?
Another question: How to get the Lagrange multiplier from mphmatrix?
Many thanks!