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C++ Reference: class ImpliedBoundsProcessor
Note: This documentation is automatically generated.
Given an upper-bounded linear relation (sum terms <= ub), this algorithm
inspects the integer variable appearing in the sum and try to replace each of
them by a tight lower bound (>= coeff * binary + lb) using the implied bound
repository. By tight, we mean that it will take the same value under the
current LP solution.
We use a class to reuse memory of the tmp terms.
| Method |
AddLpVariable | Return type: void Arguments: IntegerVariable var Add a new variable that could be used in the new cuts.
Note that the cache must be computed to take this into account.
|
DebugSlack | Return type: bool Arguments: IntegerVariable first_slack,
const LinearConstraint& initial_cut,
const LinearConstraint& cut,
const std::vector<SlackInfo>& info Only used for debugging.
Substituting back the slack created by the function above should give
exactly the same cut as the original one.
|
GetCachedImpliedBoundInfo | Return type: BestImpliedBoundInfo Arguments: IntegerVariable var |
IbCutPool | Return type: TopNCuts& As we compute the best implied bounds for each variable, we add violated
cuts here.
|
ImpliedBoundsProcessor | Arguments: absl::Span<const IntegerVariable> lp_vars_,
IntegerTrail* integer_trail,
ImpliedBounds* implied_bounds We will only replace IntegerVariable appearing in lp_vars_.
|
ProcessUpperBoundedConstraint | Return type: void Arguments:
const absl::StrongVector<IntegerVariable, double>& lp_values,
LinearConstraint* cut Processes and updates the given cut.
|
ProcessUpperBoundedConstraintWithSlackCreation | Return type: void Arguments:
bool substitute_only_inner_variables, IntegerVariable first_slack,
const absl::StrongVector<IntegerVariable, double>& lp_values,
LinearConstraint* cut, std::vector<SlackInfo>* slack_infos |
RecomputeCacheAndSeparateSomeImpliedBoundCuts | Return type: void Arguments:
const absl::StrongVector<IntegerVariable, double>& lp_values See if some of the implied bounds equation are violated and add them to
the IB cut pool if it is the case.
Important: This must be called before we process any constraints with a
different lp_values or level zero bounds.
|
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Last updated 2024-08-06 UTC.
[null,null,["Last updated 2024-08-06 UTC."],[],["The `ImpliedBoundsProcessor` class processes upper-bounded linear relations by replacing integer variables with tighter lower bounds. Key actions include: adding variables (`AddLpVariable`), processing and updating constraints (`ProcessUpperBoundedConstraint`, `ProcessUpperBoundedConstraintWithSlackCreation`), and checking for violations of implied bounds (`RecomputeCacheAndSeparateSomeImpliedBoundCuts`). It uses cached information about implied bounds (`GetCachedImpliedBoundInfo`) and stores violated cuts in a pool (`IbCutPool`). Debugging is supported with `DebugSlack`. The processor is initialized with the `lp_vars`, `integer_trail`, and `implied_bounds` in the constructor.\n"],null,[]]
