Reference documentation for deal.II version GIT relicensing693g4fb6c325db 20240521 16:20:02+00:00

#include <deal.II/numerics/time_dependent.h>
Public Member Functions  
TimeSteppingData (const unsigned int look_ahead, const unsigned int look_back)  
Public Attributes  
const unsigned int  look_ahead 
const unsigned int  look_back 
Structure holding the two basic entities that control a loop over all time steps: how many time steps ahead of the present one we shall start waking up timestep objects and how many timesteps behind we shall call their sleep
method.
Definition at line 367 of file time_dependent.h.
TimeDependent::TimeSteppingData::TimeSteppingData  (  const unsigned int  look_ahead, 
const unsigned int  look_back  
) 
Constructor; see the different fields for a description of the meaning of the parameters.
Definition at line 34 of file time_dependent.cc.
const unsigned int TimeDependent::TimeSteppingData::look_ahead 
This denotes the number of timesteps the timestepping algorithm needs to look ahead. Usually, this number will be zero, since algorithms looking ahead can't act as timestepping schemes since they can't compute their data from knowledge of the past only and are therefore global in time.
However, it may be necessary to look ahead in other circumstances, when not wanting to access the data of the next time step(s), but for example to know the next grid, the solution of a dual problem on the next time level, etc.
Note that for a dual problem walking back in time, "looking ahead" means looking towards smaller time values.
The value of this number determines, how many time steps ahead the time step manager start to call the wake_up
function for each time step.
Definition at line 394 of file time_dependent.h.
const unsigned int TimeDependent::TimeSteppingData::look_back 
This is the opposite variable to the above one. It denotes the number of time steps behind the present one for which we need to keep all data in order to do the computations on the present time level.
For one step schemes (e.g. the Euler schemes, or the CrankNicolson scheme), this value will be one.
The value of this number determines, how many time steps after having done computations on a time level the time step manager will call the sleep
function for each time step.
Definition at line 408 of file time_dependent.h.