Vega FEM Library (v1.1) User's Manual - University of Southern ...

Return the time taken in DoTimestep to generate the force/stiffness values and to solve the linear system
while timestepping, respectively. It is up to subclasses to calculate these values in DoTimestep.
virtual double GetKineticEnergy()
virtual double GetTotalMass()
Calculates and returns the kinetic energy or total mass of the simulation, based upon the mass matrix
and the velocity buffer of the class.
class ImplicitNewmarkSparse : public IntegratorBaseSparse Implements implicit Newmark integration,
and expands IntegratorBaseSparse with features common to Newmark-style integrators.
ImplicitNewmarkSparse(int r, double timestep,
SparseMatrix * massMatrix, ForceModel * forceModel,
int positiveDefiniteSolver=0, int numConstrainedDOFs=0,
int * constrainedDOFs=NULL, double dampingMassCoef=0.0,
double dampingStiffnessCoef=0.0, int maxIterations = 1,
double epsilon = 1E-6, double NewmarkBeta=0.25,
double NewmarkGamma=0.5, int numSolverThreads=0)
Initializes maxIterations, epsilon, NewmarkBeta, NewmarkGamma, and
numSolverThreads parameters, and forwards the other parameters to the
IntegratorBaseSparse constructor. For PARDISO and SPOOLES solvers, we found best performance with
2-3 threads; more threads usually decreased performance.
virtual void SetTimestep(double timestep)
Sets the timestep.
virtual int SetState(double * q, double * qvel=NULL)
Sets the position (and optionally the velocity) buffer, and calculates the acceleration buffer accordingly
using implicit Newmark, assuming no external force. Returns 0 if successful, 1 otherwise.
virtual int DoTimestep()
Runs a timestep of implicit Newmark, updating the internal position, velocity, and acceleration buffers
accordingly. Returns 0 if and only if the timestep is completed successfully.
void SetNewmarkBeta(double NewmarkBeta)
void SetNewmarkGamma(double NewmarkGamma)
Set the value of the beta and gamma parameters, respectively, for Newmark integrators. No checking is
performed to see if these values are in the appropriate range.
void UseStaticSolver(bool useStaticSolver)
Sets whether to use a static solver. The class defaults to dynamic.
class ImplicitBackwardEulerSparse : public ImplicitNewmarkSparse Replaces the DoTimestep
function of ImplicitNewmarkSparse to implement implicit Euler integration.
ImplicitBackwardEulerSparse(int r, double timestep,
SparseMatrix * massMatrix,
ForceModel * forceModel,
int positiveDefiniteSolver=0, int numConstrainedDOFs=0,
int * constrainedDOFs=NULL, double dampingMassCoef=0.0,
double dampingStiffnessCoef=0.0, int maxIterations = 1,
double epsilon = 1E-6, int numSolverThreads=0)
Sets the integrator parameters with the ImplicitNewmarkSparse constructor.
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