make_fixed_action Class Reference

Fix a variable at a specified bound. More...

#include <CoinPresolveFixed.hpp>

Inheritance diagram for make_fixed_action:

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Collaboration diagram for make_fixed_action:

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List of all members.

Classes
struct	action
	Structure to preserve the bound overwritten when fixing a variable. More...
Public Member Functions
const char *	name () const
	Returns string "make_fixed_action".
void	postsolve (CoinPostsolveMatrix *prob) const
	Postsolve (unfix variables).
	~make_fixed_action ()
	Destructor.
Static Public Member Functions
static const CoinPresolveAction *	presolve (CoinPresolveMatrix prob, int fcols, int nfcols, bool fix_to_lower, const CoinPresolveAction *next)
	Perform actions to fix variables and return postsolve object.
Private Member Functions
	make_fixed_action (int nactions, const action actions, bool fix_to_lower, const remove_fixed_action faction, const CoinPresolveAction *next)
	Constructor.
Private Attributes
int	nactions_
	Number of preserved bounds.
const action *	actions_
	Vector of preserved bounds, one for each variable fixed in this object.
const bool	fix_to_lower_
	True to fix at lower bound, false to fix at upper bound.
const remove_fixed_action *	faction_
	The postsolve object with information to undo the fix(es).
Related Functions
(Note that these are not member functions.)
const CoinPresolveAction *	make_fixed (CoinPresolveMatrix prob, const CoinPresolveAction next)
	Scan variables and fix any with equal bounds.

Detailed Description

Fix a variable at a specified bound.

Implements the action of fixing a variable by forcing both bounds to the same value and forcing the value of the variable to match.

If the bounds are already equal, and the value of the variable is already correct, consider remove_fixed_action.

Definition at line 93 of file CoinPresolveFixed.hpp.

Constructor & Destructor Documentation

make_fixed_action::make_fixed_action	(	int	nactions,
		const action *	actions,
		bool	fix_to_lower,
		const remove_fixed_action *	faction,
		const CoinPresolveAction *	next
	)			`[inline, private]`

Constructor.

Definition at line 116 of file CoinPresolveFixed.hpp.

make_fixed_action::~make_fixed_action ( ) [inline]

Destructor.

Definition at line 151 of file CoinPresolveFixed.hpp.

Member Function Documentation

const char* make_fixed_action::name ( ) const [virtual]

Returns string "make_fixed_action".

Implements CoinPresolveAction.

static const CoinPresolveAction* make_fixed_action::presolve	(	CoinPresolveMatrix *	prob,
		int *	fcols,
		int	nfcols,
		bool	fix_to_lower,
		const CoinPresolveAction *	next
	)			`[static]`

Perform actions to fix variables and return postsolve object.

For each specified variable (nfcols, fcols), fix the variable to the specified bound (fix_to_lower) by setting the variable's bounds to be equal in prob. Create a postsolve object, link it at the head of the list of postsolve objects (next), and return the object.

void make_fixed_action::postsolve ( CoinPostsolveMatrix * prob ) const [virtual]

Postsolve (unfix variables).

Back out the variables fixed by the presolve side of this object.

Implements CoinPresolveAction.