SP Constraint


# SP_Constraint

#include <domain/constraints/SP_Constraint.h>

class SP_Constraint: public DomainComponent

TaggedObject
MovableObject
DomainComponent


An SP_Constraint represents a single point constraint in the domain. A single point constraint specifies the response of a particular degree-of-freedom at a node. The declaration that all methods are virtual allows for time varying constraints to be introduced.

// Constructors



// Destructor


// Public Methods





// Public Methods for Output



To construct a single point constraint to constrain the trial displacement of the ndof’th dof at node node to the value given by value. The integer value tag is used to identify the SP_Constraint among all other SP_Constraints. If value is equal to \(0.0\) the method isHomogeneous() will always return true, otherwise false.

Provided for subclasses to use. The subclasses can vary the value of the imposed displacement when getValue() is invoked. If this constructor is used the isHomogeneous() method will always return false. The integer value tag is used to identify the SP_Constraint among all other SP_Constraints.

Provided for the FEM_ObjectBroker to be able to instantiate an object; the data for this object will be read from a Channel object when recvSelf() is invoked. \(0\) and classTag are passed to the DomainComponent constructor.


Does nothing. Provided so that a subclasses destructor can be invoked.


Returns the value of node passed in the constructor, this should be the tag of the node that is being constrained.

virtual int getDOF_Number(void) const;

Returns the value of ndof that was passed in the constructor, this identifies the dof number corresponding to the constraint.

To set the value of the constraint for the load factor given by loadFactor. The constraint is set equal to loadFactor * value if the constraint is not constant, or value if the constraint was identified as constant in the constructor.

To return a boolean indicating whether or not the constraint is a homogeneous constraint. A homogeneous constraint is one where the value of the constraint, value, is always \(0\). This information can be used by the ConstraintHandler to reduce the number of equations in the system.

virtual double getValue(void) const;

To return the value of the constraint determined in the last call to applyConstraint(). This base class returns value passed in the constructor.

To set the LoadPattern tag associated with the object to be loadPatternTag.

To return the load pattern tag associated with the load.

virtual int sendSelf(int commitTag, Channel &theChannel);

Creates a Vector, and stores the SP_Constraints tag, nodeTag, ndof and value in the Vector. It then passes the Vector as an argument to theChannel objects sendVector() method, along with the objects database tag and commitTag. Subclasses must invoke this method in their implementation of sendSelf(), so that the node and ndof values in remote object can be set. Returns \(0\) if successful, a negative number if the Channel object, theChannel, failed to send the data. virtual int recvSelf(int commitTag, Channel &theChannel, FEM_ObjectBroker &theBroker);
Creates a Vector, and receives the Vector from the channel object using the recvVector() method call and the objects own database tag and commitTag. Using the information contained in the Vector, the SP_Constraints tag, nodeTag, ndof and value are set. Subclasses must invoke this method in their implementation of recvSelf(), so that the node and ndof values can be set. Returns \(0\) if successful, a negative number if the Channel object, theChannel, failed to receive the data.

virtual void Print(OPS_Stream &s, int flag = 0) const;

Prints out the SP_Constraints tag, then node, ndof and value.

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