8.2.2. MdoCons

class mindopt::MdoCons

Constraint object.

This object implements the data structure to hold an optimization constraint. An empty constraint object by calling MdoModel::addCons(). Once created, users may modify its left-hand-side value or right-hand-side value by calling MdoCons::setRealAttr() with a proper real-valued model attribute.

Note

Do not use constructor (MdoVar::MdoCons()) to create an empty constraint object.

Examples

/* Create an empty model. */
MdoModel model;

MdoI32 itmp = 0;
MdoReal dtmp = 0.0;
std::string ctmp;

/* Add empty constraints. */
std::vector<std::reference_wrapper<MdoCons> > cons;
cons.push_back(model.addCons(1.0, 1.0,           "c0"));
cons.push_back(model.addCons(1.0, MDO_INFINITY,  "c1"));

/* Input columns. */
std::vector<MdoCol> col(4);
col[0].addTerm(cons[0], 1.0);
col[0].addTerm(cons[1], 1.0);
col[1].addTerm(cons[0], 1.0);
col[2].addTerm(cons[0], 2.0);
col[2].addTerm(cons[1], -1.0);
col[3].addTerm(cons[0], 3.0);
col[3].addTerm(cons[1], 6.0);

/* Check constraint object */
MdoCons c0 = model.getCons(0);
itmp = cons[0].get().sameAs(c0);
std::string c0_name = c0.getStrAttr("RowName");
MdoCons c0_2 = model.getCons(c0_name);
itmp = cons[0].get().sameAs(c0_2);
itmp = c0.getIndex();

/* Set/get attribute */
cons[1].setIntAttr("RowBasis", 1);
itmp = cons[1].get().getIntAttr("RowBasis");
cons[1].get().setRealAttr("LHS", -5.0);
dtmp = cons[1].get().getRealAttr("LHS");
cons[1].get().setStrAttr("RowName", row_name);
ctmp = cons[1].get().getStrAttr("RowName");

Constructor / destructor.

MdoCons(void)

Default constructor.

MdoCons(MdoMdlPtr model, MdoI32 index)

Constructor with argument.

Parameters

  • model – Pointer to the optimization model.

  • index – Constraint index.

virtual ~MdoCons(void)

Destructor.

MdoCons(const MdoCons &rhs)

Copy constructor.

Parameters

rhs – Object to copy.

Basic operators.

MdoCons &operator=(const MdoCons &rhs)

Assignment operator.

Parameters

rhs – Object to copy.

Return

Updated object.

Functions to access the internal data.

MdoI32 getIndex(void) const

This function returns the current index of the constraint in the optimization model.

Return

The current index of the constraint in the optimization model.

MdoBool sameAs(const MdoCons &rhs) const

This function checks whether two constraint objects refer to the same constraint.

Parameters

rhs – Another constraint object.

Return

A boolean flag indicates if two constraint objects refer to the same constraint.

void setStrAttr(std::string att, std::string val)

This function changes the value of a string-valued row attribute.

Parameters

  • att – A string-valued row attribute to access.

  • val – A new value for the string-valued row attribute.

std::string getStrAttr(std::string att) const

This function returns the value of a string-valued row attribute.

Parameters

att – A string-valued row attribute to access.

Return

The value of a string-valued row attribute.

void setIntAttr(std::string att, MdoI32 val)

This function changes the value of an integer-valued row attribute.

Parameters

  • att – An integer-valued row attribute to access.

  • val – A new value.

MdoI32 getIntAttr(std::string att) const

This function returns the value of an integer-valued row attribute.

Parameters

att – An integer-valued row attribute to access.

Return

The value of an integer-valued row attribute.

void setRealAttr(std::string att, MdoReal val)

This function changes the value of a real-valued row attribute.

Parameters

  • att – A real-valued row attribute to access.

  • val – A new value.

MdoReal getRealAttr(std::string att) const

This function retrieves the value of a real-valued row attribute.

Parameters

att – A real-valued row attribute to access.

Return

The value of a real-valued row attribute.