Ranking Goals

INDEX PREVIOUS NEXT

A set of instances of IloResourceConstraint may be ranked (ordered along the time line) for a resource which defines a mutually exclusive relationship between activities that require it. Ranking is defined for the classes IloUnaryResource and IloStateResource.

Ranking is possible for any resource constraint with an IloFromStartToEnd time extent.

• resource constraints already chronologically ranked;
• resource constraints which can be ranked first, that is, which can be positioned at the head of the not ranked constraints;
• resource constraints which cannot be ranked first, that is, another not ranked resource constraint will necessarily be positioned at the head of the not ranked constraints.

See Figure 2.1.

• IloGoal IloRankForward(const IloEnv env,
const IloUnaryResource resource);
  Returns a goal that ranks all resource constraints of the unary resource resource. The duration and capacity required by the activities is assumed to be bounded. By default, the resource constraint selector IloSelFirstRCMinStartMax selects the next resource constraint to be ranked first.
• IloGoal IloRankForward(const IloEnv env,
const IloStateResource resource);
  Returns a goal that ranks all resource constraints of the state resource resource. The duration required by the activities is assumed to be bounded. By default, the resource constraint selector IloSelFirstRCMinStartMax selects the next resource constraint to be ranked first.
• IloGoal IloRankForward(const IloEnv env);
  Returns a goal that ranks all resource constraints of all unary resources in the model whose capacity constraints are not ignored (see IloResourceParam in the IBM ILOG Scheduler Reference Manual). By default the next resource to be ranked is chosen by the selector IloSelResMinGlobalSlack and the next resource constraint on the resource is selected by the selector IloSelFirstRCMinStartMax.
• IloGoal IloRankForward(const IloEnv env,
const IloNumVar criterion);
  Returns a goal that ranks all resource constraints of all unary or state resources in the model whose capacity constraints are not ignored (see IloResourceParam in the IBM ILOG Scheduler Reference Manual), while minimizing criterion. By default, the next resource to be ranked is chosen by the selector IloSelResMinGlobalSlack and the next resource constraint on the resource is selected by the selector IloSelFirstRCMinStartMax.
• IloGoal IloRankBackward(const IloEnv env,
const IloUnaryResource resource);
  Returns a goal that ranks all resource constraints of the unary resource resource. The duration and capacity required by the activities are assumed to be bounded. By default, the resource constraint selector IloSelLastRCMaxEndMin selects the next resource constraint to be ranked last.
• IloGoal IloRankBackward(const IloEnv env,
const IloStateResource resource);
  Returns a goal that ranks all resource constraints of the state resource resource. The duration required by the activities are assumed to be bounded. By default, the resource constraint selector IloSelLastRCMaxEndMin selects the next resource constraint to be ranked last.
• IloGoal IloRankBackward(const IloEnv env);
  Returns a goal that ranks all resource constraints of all unary resources in the model whose capacity constraints are not ignored (see IloResourceParam in the IBM ILOG Scheduler Reference Manual). By default the next resource to be ranked backward is chosen by the selector IloSelResMinGlobalSlack and the next resource constraint on the resource is selected by the selector IloSelLastRCMaxEndMin.
• IloGoal IloRankBackward(const IloEnv env,
const IloNumVar criterion);
  Returns a goal that ranks all resource constraints of all unary or state resources in the model whose capacity constraints are not ignored (see IloResourceParam in the IBM ILOG Scheduler Reference Manual), while maximizing criterion. By default the next resource to be ranked backward is chosen by the IloSelResMinGlobalSlack selector and the next resource constraint on the resource is selected by the IloSelLastRCMaxEndMin selector.