Parameters used in the LP process. More...
#include <BCP_lp_param.hpp>
Parameters used in the LP process.
These parameters can be set in the original parameter file by including the following line:
BCP_{parameter name} {parameter value}
.
Definition at line 14 of file BCP_lp_param.hpp.
Character parameters.
All of these variables are used as booleans (true = 1, false = 0).
BranchOnCuts |
If true, BCP supports branching on cuts by providing potential branching candidates for the user. These are cuts that were added to the formulation at some point but became slack later in subsequent LP relaxations. |
CompareNewCutsToOldOnes |
If true then the LP process will check each newly received cut whether it already exists in the local cut pool or not.
|
CompareNewVarsToOldOnes |
If true then the LP process will check each newly arrived variable whether it already exists in the local variable pool or not.
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DoReducedCostFixingAtZero |
If true the BCP will attempt to do reduced cost fixing only for variables currently at zero.
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DoReducedCostFixingAtAnything |
If true the BCP will attempt to do reduced cost fixing for any variable, no matter what is their current value.
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MaintainIndexedVarPricingList |
Indicate whether BCP is supposed to track the indexed variables yet to be priced out. |
MessagePassingIsSerial |
Indicates whether message passing is serial (all processes are on the same processor) or not.
|
ReportWhenDefaultIsExecuted |
Print out a message when the default version of an overridable method is executed. Default: 1. |
SendFathomedNodeDesc |
Whether to send back the description of fathomed search tree nodes to the Tree Manager. (Might be needed to write proof of optimality.) |
NoCompressionAtFathom |
Whether we should refrain from compressing the problem description right before a fathomed node's description is sent back to the tree manager.
|
LpVerb_First |
Just a marker for the first LpVerb. |
LpVerb_AddedCutCount |
Print the number of cuts added from the local cut pool in the current iteration. (BCP_lp_main_loop) |
LpVerb_AddedVarCount |
Print the number of variables added from the local variable pool in the curent iteration. (BCP_lp_main_loop) |
LpVerb_ChildrenInfo |
After a branching object is selected print what happens to the presolved children (e.g., fathomed). (BCP_print_brobj_stat) |
LpVerb_ColumnGenerationInfo |
Print the number of variables generated before resolving the Lp ir fathoming a node. (BCP_lp_fathom) |
LpVerb_CutsToCutPoolCount |
Print the number of cuts sent from the LP to the cut pool. (BCP_lp_send_cuts_to_cp) |
LpVerb_VarsToVarPoolCount |
**** This parameter is not used anywhere!!! **** |
LpVerb_FathomInfo |
Print information related to fathoming. (BCP_lp_main_loop, BCP_lp_perform_fathom, BCP_lp_branch) (BCP_lp_fathom) |
LpVerb_IterationCount |
Print the "Starting iteration x" line. (BCP_lp_main_loop) |
LpVerb_RelaxedSolution |
Turn on the user hook "display_lp_solution". (BCP_lp_main_loop) |
LpVerb_FinalRelaxedSolution |
Turn on the user hook "display_lp_solution" for the last LP relaxation solved at a search tree node. (BCP_lp_main_loop) |
LpVerb_LpMatrixSize |
**** This parameter is not used anywhere!!! **** |
LpVerb_LpSolutionValue |
Print the size of the problem matrix and the LP solution value after resolving the LP. (BCP_lp_main_loop) |
LpVerb_MatrixCompression |
Print the number of columns and rows that were deleted during matrix compression. (BCP_lp_delete_cols_and_rows) |
LpVerb_NodeTime |
For each tree node print out how much time was spent on it. |
LpVerb_PresolvePositions |
Print detailed information about all the branching candidates during strong branching. LpVerb_PresolveResult must be set for this parameter to have an effect. (BCP_lp_perform_strong_branching) |
LpVerb_PresolveResult |
Print information on the presolved branching candidates during strong branching. (BCP_lp_perform_strong_branching) |
LpVerb_ProcessedNodeIndex |
Print the "Processing NODE x on LEVEL y" line. (BCP_lp-main_loop) |
LpVerb_ReportCutGenTimeout |
Print information if receiving cuts is timed out. (BCP_lp_generate_cuts) |
LpVerb_ReportVarGenTimeout |
Print information if receiving variables is timed out. (BCP_lp_generate_vars) |
LpVerb_ReportLocalCutPoolSize |
Print the current number of cuts in the cut pool. This number is printed several times: before and after generating columns at the current iteration, after removing non-essential cuts, etc. (BCP_lp_generate_cuts) |
LpVerb_ReportLocalVarPoolSize |
Similar as above for variables. (BCP_lp_generate_vars) |
LpVerb_RepricingResult |
**** This parameter is not used anywhere!!! **** |
LpVerb_VarTightening |
Print the number of variables whose bounds have been changed by reduced cost fixing or logical fixing. (BCP_lp_fix_vars) |
LpVerb_RowEffectivenessCount |
Print the number of ineffective rows in the current problem. The definition of what rows are considered ineffective is determined by the paramter IneffectiveConstraints. (BCP_lp_adjust_row_effectiveness) |
LpVerb_StrongBranchPositions |
Print detailed information on the branching candidate selected by strong branching. LpVerb_StrongBranchResult must be set fo this parameter to have an effect. (BCP_print_brobj_stat) |
LpVerb_StrongBranchResult |
Print information on the branching candidate selected by strong branching. (BCP_print_brobj_stat) |
LpVerb_GeneratedCutCount |
Print the number of cuts generated during this iteration (since the LP was resolved last time). (BCP_lp_main_loop) |
LpVerb_GeneratedVarCount |
Print the number of variables generated during this iteration. (BCP_lp_main_loop) |
LpVerb_Last |
Just a marker for the last LpVerb. |
end_of_chr_params |
Reimplemented in BCP_parameter_set< BCP_lp_par >.
Definition at line 17 of file BCP_lp_param.hpp.
Integer parameters.
NiceLevel |
What should be the "niceness" of the LP process. In a *nix environment the LP process will be reniced to this level. |
ScaleMatrix |
Indicates how matrix scaling should be performed. This parameter is directly passed to the LP solver's |
IndexedToPriceStorageSize |
Indicates the number of entries stored in a
|
SlackCutDiscardingStrategy |
The slack cut discarding strategy used in the default version of the function
|
CutEffectiveCountBeforePool |
A cut has to remain effective through this many iterations in the LP before it is sent to the Cut Pool process.
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CutPoolCheckFrequency |
The Cut Pool is queried for violated valid inequalities after the first LP relaxation is solved and then after every this many iterations.
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VarPoolCheckFrequency |
The Variable Pool is queried for columns that improve the formulation after the first LP realxation is solved, and then after every this many iterations.
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IneffectiveConstraints |
Indicates which constraints should be considered ineffective.
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IneffectiveBeforeDelete |
How many times in a row a constraint must be found ineffective before it is marked for deletion.
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MaxNonDualFeasToAdd_Min |
The number of non dual-feasible colums that can be added at a time to the formulation is a certain fraction ( However, if the computed number is outside of the range |
MaxNonDualFeasToAdd_Max |
See the description of the previous parameter.
|
MaxIndexedToPriceToAdd_Min |
When the tableau is total dual feasible some of variables from the list of the not yet fixed indexed variables are added to the formulation so that the list can be shorter in the descendant nodes (or may become empty). These parameters play the same role in limiting the number of such variables as the two previous parameters for the non dual feasible variables. |
MaxIndexedToPriceToAdd_Max |
See the description of the previous parameter.
|
CutViolationNorm |
How cut violation should be computed.
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MaxCutsAddedPerIteration |
The maximum number of violated valid inequalities that can be added per iteration.
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MaxVarsAddedPerIteration |
The maximum number of variables that can be added per iteration.
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MaxLeftoverCutNum |
The maximum number of violated but not added cuts to be kept from one iteration to the next. Also see the MaxLeftoverCutFrac parameter. |
DeletedColToCompress_Min |
The number of columns that must be marked for deletion before matrix compression can occur. Matrix compressions also subject to a minimum number of marked columns as a fraction of the current number of columns (see |
DeletedRowToCompress_Min |
The number of rows that must be marked for deletion before matrix compression can occur. Matrix compressionis also subject to a minimum number of marked columns as a fraction of the current number of columns (see |
MaxPresolveIter |
Upper limit on the number of iterations performed in each of the children of the search tree node when presolving branching candidates. This parameter is passed onto the LP solver. If the parameter is set to -1 then the branching candidates are not presolved and the first branching candidate is chosen (if there is any). |
StrongBranch_CloseToHalfNum |
Specifies how many branching variables with values close to half between two integers should be chosen by the built-in branching variable selection routine This number is passed onto the |
StrongBranch_CloseToOneNum |
Specifies how many branching variables with values close to an integer should be chosen by the built-in branching variable selection routine This number is passed onto the |
BranchingObjectComparison |
Specifies the rule used for built-in branching object comparison (if the buit-in routine is used at all).
|
ChildPreference |
Specifies the rule used for selecting one of the children of the search tree node for diving.
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FeasibilityTest |
Specifies which built-in MIP feasibility testing routine should be invoked (if a buit-in routine is used at all).
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InfoForCG |
Indicates what part of the primal solution is sent to the Cut Generator process if the BCP_lp_user::pack_primal_solution() method is not overridden.
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InfoForVG |
Indicates what part of the dual solution is sent to the Variable Generator process if the BCP_lp_user::pack_dual_solution() method is not overridden.
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end_of_int_params |
Reimplemented in BCP_parameter_set< BCP_lp_par >.
Definition at line 162 of file BCP_lp_param.hpp.
Double parameters.
Granularity |
The minimum difference between the objective value of any two feasible solution (with different objective values).
|
DeletedColToCompress_Frac |
The fraction of columns that must be marked for deletion before matrix compression can occur. Matrix compression is also subject to a minimum number of marked columns (see |
DeletedRowToCompress_Frac |
The fraction of rows that must be marked for deletion before matrix compression can occur. Matrix compression is also subject to a minimum number of marked rows (see |
MaxNonDualFeasToAdd_Frac |
The number of non dual-feasible colums that can be added to the formulation at a time cannot exceed this fraction of the the number of columns in the curent formulation. However, this limit can be overruled by the hard bounds |
MaxIndexedToPriceToAdd_Frac |
When the tableau is total dual feasible and variables from the list of the not yet fixed indexed variables are added to the formulation, the number of such columns is limited to this fraction of the columns currently in the formulation. However, this limit might be overruled by the hard bounds |
MaxLeftoverCutFrac |
The maximum fraction of the violated but not added cuts to be kept from one iteration to the next. Also see the MaxLeftoverCutNum parameter. |
IntegerTolerance |
Values not further from an integer value than the value of this parameter are considered to be integer.
|
FirstLP_FirstCutTimeout |
This and the following three parameters control how long the LP process waits for generated cuts. The parameters specify waiting times (in seconds) separately for the first and later LP relaxations at a search tree node, and also the time to receive the first cut vs all the cuts. |
LaterLP_FirstCutTimeout |
This parameter specifies the time to wait for the first generated cut at iterations that are not the first at a search tree node. See the remarks at |
FirstLP_AllCutsTimeout |
This parameter specifies the time to wait for cuts at the first LP relaxation at a search tree node. See the remarks at |
LaterLP_AllCutsTimeout |
This parameter specifies the time to wait for cuts at iterations that are not the first at a search tree node. See the remarks at |
FirstLP_FirstVarTimeout |
This and the following three parameters control how long the LP process waits for generated variables. These parameters are analogous to the ones that control the waiting time for generated cuts. See the remarks at |
LaterLP_FirstVarTimeout |
This parameter specifies the time to wait for the first generated variable at iterations that are not the first at a search tree node. See the remarks at |
FirstLP_AllVarsTimeout |
This parameter specifies the time to wait for variables at the first LP relaxation at a search tree node. See the remarks at |
LaterLP_AllVarsTimeout |
This parameter specifies the time to wait for variables at iterations that are not the first at a search tree node. See the remarks at |
end_of_dbl_params |
Reimplemented in BCP_parameter_set< BCP_lp_par >.
Definition at line 329 of file BCP_lp_param.hpp.
String parameters.
Reimplemented in BCP_parameter_set< BCP_lp_par >.
Definition at line 447 of file BCP_lp_param.hpp.
There are no string array parameters.
Reimplemented in BCP_parameter_set< BCP_lp_par >.
Definition at line 455 of file BCP_lp_param.hpp.