`specfem::time_scheme::time_scheme`¶

class time_scheme¶

Base class for time integration schemes.

Provides the interface for time-stepping algorithms in wave propagation simulations. Handles forward and backward time integration, seismogram output control, and predictor-corrector phases.

Derived classes implement specific integration schemes (e.g., newmark).

Subclassed by specfem::time_scheme::newmark< AssemblyFields, specfem::simulation::type::combined >, specfem::time_scheme::newmark< AssemblyFields, specfem::simulation::type::forward >

Constructors

inline time_scheme(const int nstep, const int nstep_between_samples, const type_real dt)¶

Construct time scheme.

Parameters:

nstep – Number of timesteps
nstep_between_samples – Number of timesteps between seismogram samples
dt – Time step

Iterators

inline impl::ForwardRange iterate_forward()¶

Forward iterator.

/// increments time step
for (const auto [istep, dt] : ts.iterate_forward()) {
  const auto time = istep * dt; /// Computing the current time
}

Returns:: std::tuple<int, type_real> Tuple of current timestep (istep) and time increment (dt)

inline impl::BackwardRange iterate_backward()¶

Backward iterator.

/// decrements time step
for (const auto [istep, dt] : ts.iterate_backward()) {
  const auto time = istep * dt; /// Computing the current time
}

Returns:: std::tuple<int, type_real> Tuple of current timestep (istep) and time increment (dt)

Public Functions

inline int get_max_timestep()¶

Get the max timestep.

Returns:: int Maximum number of timesteps

inline void increment_seismogram_step()¶: Increment seismogram output step.

inline bool compute_seismogram(const int istep) const¶

Checks if seismogram should be computed at current timestep.

Parameters:: istep – Current timestep
Returns:: bool True if seismogram should be computed

inline int get_seismogram_step() const¶

Get the current seismogram step.

Returns:: int Seismogram timestep

inline int get_max_seismogram_step() const¶

Get the maximum seismogram step.

Returns:: int Maximum seismogram step

inline int get_nstep_between_samples() const¶

Get the number of timesteps between seismogram samples.

Returns:: int Number of timesteps between seismogram samples

virtual int apply_predictor_phase_forward(const specfem::element::medium_tag tag) = 0¶

Apply predictor phase for forward time integration.

Updates displacement and velocity using current acceleration for the forward wavefield. Pure virtual method implemented by derived classes.

Parameters:: tag – Medium type to process (elastic, acoustic, etc.)
Returns:: Number of degrees of freedom updated

virtual int apply_corrector_phase_forward(const specfem::element::medium_tag tag) = 0¶

Apply corrector phase for forward time integration.

Updates velocity using newly computed acceleration for the forward wavefield. Pure virtual method implemented by derived classes.

Parameters:: tag – Medium type to process (elastic, acoustic, etc.)
Returns:: Number of degrees of freedom updated

virtual int apply_predictor_phase_backward(const specfem::element::medium_tag tag) = 0¶

Apply predictor phase for backward time integration.

Updates displacement and velocity using current acceleration for the backward wavefield. Pure virtual method implemented by derived classes.

Parameters:: tag – Medium type to process (elastic, acoustic, etc.)
Returns:: Number of degrees of freedom updated

virtual int apply_corrector_phase_backward(const specfem::element::medium_tag tag) = 0¶

Apply corrector phase for backward time integration.

Updates velocity using newly computed acceleration for the backward wavefield. Pure virtual method implemented by derived classes.

Parameters:: tag – Medium type to process (elastic, acoustic, etc.)
Returns:: Number of degrees of freedom updated

virtual specfem::enums::time_scheme::type timescheme() const = 0¶

Get the time scheme type.

Returns:: Type of time integration scheme (e.g., Newmark)

virtual std::string to_string() const = 0¶

Convert time scheme to string representation.

Returns:: String describing the time scheme configuration

virtual void print(std::ostream &out) const = 0¶

Print time scheme details to output stream.

Parameters:: out – Output stream

virtual type_real get_timestep() const = 0¶

Get the time increment per step.

Returns:: Time step size

specfem::time_scheme::time_scheme¶

`specfem::time_scheme::time_scheme`¶