TSSetFromOptions#

Sets various TS parameters from the options database

Synopsis#

#include "petscts.h"  
PetscErrorCode TSSetFromOptions(TS ts)

Collective

Input Parameter#

ts - the TS context obtained from TSCreate()

Options Database Keys#

-ts_type - EULER, BEULER, SUNDIALS, PSEUDO, CN, RK, THETA, ALPHA, GLLE, SSP, GLEE, BSYMP, IRK, see TSType
-ts_save_trajectory - checkpoint the solution at each time-step
-ts_max_time - maximum time to compute to
-ts_time_span <t0,…tf> - sets the time span, solutions are computed and stored for each indicated time
-ts_max_steps - maximum number of time-steps to take
-ts_init_time - initial time to start computation
-ts_final_time - final time to compute to (deprecated: use -ts_max_time)
-ts_dt
- initial time step
-ts_exact_final_time <stepover,interpolate,matchstep> - whether to stop at the exact given final time and how to compute the solution at that time
-ts_max_snes_failures - Maximum number of nonlinear solve failures allowed
-ts_max_reject - Maximum number of step rejections before step fails
-ts_error_if_step_fails <true,false> - Error if no step succeeds
-ts_rtol - relative tolerance for local truncation error
-ts_atol - Absolute tolerance for local truncation error
-ts_rhs_jacobian_test_mult - mat_shell_test_mult_view - test the Jacobian at each iteration against finite difference with RHS function
-ts_rhs_jacobian_test_mult_transpose - test the Jacobian at each iteration against finite difference with RHS function
-ts_adjoint_solve <yes,no> - After solving the ODE/DAE solve the adjoint problem (requires -ts_save_trajectory)
-ts_fd_color - Use finite differences with coloring to compute IJacobian
-ts_monitor - print information at each timestep
-ts_monitor_cancel - Cancel all monitors
-ts_monitor_lg_solution - Monitor solution graphically
-ts_monitor_lg_error - Monitor error graphically
-ts_monitor_error - Monitors norm of error
-ts_monitor_lg_timestep - Monitor timestep size graphically
-ts_monitor_lg_timestep_log - Monitor log timestep size graphically
-ts_monitor_lg_snes_iterations - Monitor number nonlinear iterations for each timestep graphically
-ts_monitor_lg_ksp_iterations - Monitor number nonlinear iterations for each timestep graphically
-ts_monitor_sp_eig - Monitor eigenvalues of linearized operator graphically
-ts_monitor_draw_solution - Monitor solution graphically
-ts_monitor_draw_solution_phase <xleft,yleft,xright,yright> - Monitor solution graphically with phase diagram, requires problem with exactly 2 degrees of freedom
-ts_monitor_draw_error - Monitor error graphically, requires use to have provided TSSetSolutionFunction()
-ts_monitor_solution [ascii binary draw][:filename][:viewerformat] - monitors the solution at each timestep
-ts_monitor_solution_interval - output once every interval (default=1) time steps
-ts_monitor_solution_vtk <filename.vts,filename.vtu> - Save each time step to a binary file, use filename-%%03” PetscInt_FMT “.vts (filename-%%03” PetscInt_FMT “.vtu)
-ts_monitor_envelope - determine maximum and minimum value of each component of the solution over the solution time

Notes#

See SNESSetFromOptions() and KSPSetFromOptions() for how to control the nonlinear and linear solves used by the time-stepper.

Certain SNES options get reset for each new nonlinear solver, for example -snes_lag_jacobian its and -snes_lag_preconditioner its, in order to retain them over the multiple nonlinear solves that TS uses you mush also provide -snes_lag_jacobian_persists true and -snes_lag_preconditioner_persists true