CoinUtils
2.10.13
|
Fix a variable at a specified bound. More...
#include <CoinPresolveFixed.hpp>
Public Member Functions | |
const char * | name () const |
Returns string "make_fixed_action". More... | |
void | postsolve (CoinPostsolveMatrix *prob) const |
Postsolve (unfix variables) More... | |
virtual | ~make_fixed_action () |
Destructor. More... | |
![]() | |
CoinPresolveAction (const CoinPresolveAction *next) | |
Construct a postsolve object and add it to the transformation list. More... | |
void | setNext (const CoinPresolveAction *nextAction) |
modify next (when building rather than passing) More... | |
virtual | ~CoinPresolveAction () |
Virtual destructor. More... | |
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. More... | |
![]() | |
static void | throwCoinError (const char *error, const char *ps_routine) |
Stub routine to throw exceptions. More... | |
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. More... | |
void | transferCosts (CoinPresolveMatrix *prob) |
Transfer costs from singleton variables. More... | |
Additional Inherited Members | |
![]() | |
const CoinPresolveAction * | next |
The next presolve transformation. More... | |
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 95 of file CoinPresolveFixed.hpp.
|
inlinevirtual |
Destructor.
Definition at line 153 of file CoinPresolveFixed.hpp.
|
virtual |
Returns string "make_fixed_action".
Implements CoinPresolveAction.
|
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.
|
virtual |
Postsolve (unfix variables)
Back out the variables fixed by the presolve side of this object.
Implements CoinPresolveAction.
|
related |
Scan variables and fix any with equal bounds.
A front end to collect a list of columns with equal bounds and hand them to make_fixed_action::presolve() for processing.
|
related |
Transfer costs from singleton variables.
Transfers costs from singleton variables in equalities onto the other variables. Will also transfer costs from one integer variable to other integer variables with zero cost if there's a net gain in integer variables with non-zero cost.
The relation to make_fixed_action is tenuous, but this transform should be attempted before the initial round of variable fixing.