Description

Class for representing an N-DOF item with mass matrix and associated variables.

This class creates an NxN generic, dense mass matrix. While this type of variables could be used for a rigid body (with N=6), it is more efficient to create specialized classes which do not use a full 6x6 matrix, but rather manage only non-zero entries in the mass matrix of a rigid body (i.e., the mass, inertia moments, and inertia products).

#include <ChVariablesGeneric.h>

Inheritance diagram for chrono::ChVariablesGeneric:

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Collaboration diagram for chrono::ChVariablesGeneric:

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Public Member Functions
	ChVariablesGeneric (unsigned int dof=1)

ChVariablesGeneric &	operator= (const ChVariablesGeneric &other)
	Assignment operator: copy from other object.

ChMatrixDynamic &	GetMass ()
	Access the inertia matrix.

ChMatrixDynamic &	GetInvMass ()
	Access the inverted inertia matrix.

virtual void	ComputeMassInverseTimesVector (ChVectorRef result, ChVectorConstRef vect) const override
	Compute the product of the inverse mass matrix by a given vector and store in result. More...

virtual void	AddMassTimesVector (ChVectorRef result, ChVectorConstRef vect) const override
	Compute the product of the mass matrix by a given vector and increment result. More...

virtual void	AddMassTimesVectorInto (ChVectorRef result, ChVectorConstRef vect, const double ca) const override
	Add the product of the mass submatrix by a given vector, scaled by ca, to result. More...

virtual void	AddMassDiagonalInto (ChVectorRef result, const double ca) const override
	Add the diagonal of the mass matrix, as a vector scaled by ca, to result. More...

virtual void	PasteMassInto (ChSparseMatrix &mat, unsigned int start_row, unsigned int start_col, const double ca) const override
	Write the mass submatrix for these variables into the specified global matrix at the offsets of each variable. More...

Public Member Functions inherited from chrono::ChVariables
	ChVariables (unsigned int dof)

ChVariables &	operator= (const ChVariables &other)
	Assignment operator: copy from other object.

void	SetDisabled (bool mdis)
	Deactivates/freezes the variable (these variables won't be modified by the system solver).

bool	IsDisabled () const
	Check if the variables have been deactivated (these variables won't be modified by the system solver).

bool	IsActive () const
	Check if these variables are currently active. More...

unsigned int	GetDOF () const
	The number of scalar variables in the vector qb (dof=degrees of freedom).

ChVectorRef	State ()
	Get a reference to the differential states encapsulated by these variables. More...

ChVectorRef	Force ()
	Get a reference to the generalized force corresponding to these variables. More...

void	SetOffset (unsigned int moff)
	Set offset in the global state vector. More...

unsigned int	GetOffset () const
	Get offset in the global state vector.

virtual void	ArchiveOut (ChArchiveOut &archive_out)

virtual void	ArchiveIn (ChArchiveIn &archive_in)

Additional Inherited Members
Protected Attributes inherited from chrono::ChVariables
unsigned int	offset
	offset in global q state vector (needed by some solvers)

unsigned int	ndof
	number of degrees of freedom (number of contained scalar variables)

Member Function Documentation

◆ AddMassDiagonalInto()

void chrono::ChVariablesGeneric::AddMassDiagonalInto	(	ChVectorRef	result,
		const double	ca
	)		const

overridevirtual

Add the diagonal of the mass matrix, as a vector scaled by ca, to result.

Note: 'result' is a system-level vector of appropriate size. This function must index into this vector using the offsets of each variable.

Implements chrono::ChVariables.

◆ AddMassTimesVector()

void chrono::ChVariablesGeneric::AddMassTimesVector	(	ChVectorRef	result,
		ChVectorConstRef	vect
	)		const

overridevirtual

Compute the product of the mass matrix by a given vector and increment result.

This function must perform the operation result += M * vect for a vector of same size as the variables state.

Implements chrono::ChVariables.

◆ AddMassTimesVectorInto()

void chrono::ChVariablesGeneric::AddMassTimesVectorInto	(	ChVectorRef	result,
		ChVectorConstRef	vect,
		const double	ca
	)		const

overridevirtual

Add the product of the mass submatrix by a given vector, scaled by ca, to result.

Note: 'result' and 'vect' are system-level vectors of appropriate size. This function must index into these vectors using the offsets of each variable.

Implements chrono::ChVariables.

◆ ComputeMassInverseTimesVector()

void chrono::ChVariablesGeneric::ComputeMassInverseTimesVector	(	ChVectorRef	result,
		ChVectorConstRef	vect
	)		const

overridevirtual

Compute the product of the inverse mass matrix by a given vector and store in result.

This function must calculate result = M^(-1) * vect for a vector of same size as the variables state.

Implements chrono::ChVariables.

◆ PasteMassInto()

void chrono::ChVariablesGeneric::PasteMassInto	(	ChSparseMatrix &	mat,
		unsigned int	start_row,
		unsigned int	start_col,
		const double	ca
	)		const

overridevirtual

Write the mass submatrix for these variables into the specified global matrix at the offsets of each variable.

The masses will be scaled by the given factor 'ca'. The (start_row, start_col) pair specifies the top-left corner of the system-level mass matrix in the provided matrix. Assembling the system-level sparse matrix is required only if using a direct sparse solver or for debugging/reporting purposes.

Implements chrono::ChVariables.

The documentation for this class was generated from the following files:

/builds/uwsbel/chrono/src/chrono/solver/ChVariablesGeneric.h
/builds/uwsbel/chrono/src/chrono/solver/ChVariablesGeneric.cpp

Description

Public Member Functions

Additional Inherited Members

Member Function Documentation

◆ AddMassDiagonalInto()

◆ AddMassTimesVector()

◆ AddMassTimesVectorInto()

◆ ComputeMassInverseTimesVector()

◆ PasteMassInto()