Try running this: make -f ./gmakefile test search="snes_tutorials-ex13_2d_p1_conv" EXTRA_OPTIONS="-potential_petscspace_degree 3 -potential_petscdualspace_lagrange_node_type equispaced -petscds_view ::ascii_info_detail"
You see that # > Dual basis vector 0 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (-0.333333, -0.333333) +1 # > Dual basis vector 1 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (-0.25, -1) +1 # > Dual basis vector 2 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (+0.25, -1) +1 # > Dual basis vector 3 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (+0.25, -0.25) +1 # > Dual basis vector 4 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (-0.25, +0.25) +1 # > Dual basis vector 5 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (-1, +0.25) +1 # > Dual basis vector 6 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (-1, -0.25) +1 # > Dual basis vector 7 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (-1, -1) +1 # > Dual basis vector 8 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (+1, -1) +1 # > Dual basis vector 9 # > Quadrature on a unknown of order -1 on 1 points (dim 2) # > p0 (-1, +1) +1 but I think those should be +- 1/3, not 1/4. What is going on? Thanks, Matt -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://urldefense.us/v3/__https://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!fI65LTR-Ea3-N-4r5ysM7tfuF8x0HWBmgM91cUzwBlzlqmBsWUF6Q6SuBg8xfMYfeNMCmTPUU-Ffmvwm-fnI$ <https://urldefense.us/v3/__http://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!fI65LTR-Ea3-N-4r5ysM7tfuF8x0HWBmgM91cUzwBlzlqmBsWUF6Q6SuBg8xfMYfeNMCmTPUU-FfmsCeTj9Y$ >