1 2% Runs the heat equation solver for several mesh spacing and determines the order of accuracy of the method with respect to time 3 4n = 5; 5u = cell(n,1); 6for i=1:n 7 system(['./biharmonic -ts_monitor -snes_vi_monitor -pc_type lu -vi -snes_max_it 250 -snes_converged_reason -snes_linesearch_minlambda 1.e-30 -ts_type beuler -da_refine ' int2str(i+4) ' -kappa .00001 -ts_time_step 5.96046e-06 -ts_monitor_solution -ts_monitor_solution_initial -ksp_monitor_true_residual -snes_linesearch_monitor -ts_max_time .011 -ts_max_steps 10']) 8% system(['./biharmonic -ts_monitor -snes_linesearch_monitor -snes_vi_monitor -ksp_monitor_true_residual -snes_max_it 250 -snes_vi_type ss -snes_linesearch_minlambda 1.e-30 -snes_rtol 1.e-25 -snes_atol 1.e-15 -pc_type lu -vi -snes_converged_reason -ts_type cn -da_refine ' int2str(i+4) ' -kappa .00001 -ts_time_step 2.96046e-07 -ts_max_time 1. -ts_max_steps 30']) 9 ii = 2^(i-1); 10ut = PetscBinaryRead('binaryoutput');%,'precision','float128'); 11 u{i} = ut(1:ii:(320*ii)); 12end 13 14ustar = (4*u{n} - u{n-1})/3; 15 16for i=1:n 17 norm(ustar - u{i}) 18end 19 20 21