Ceron, Rodrigo 14 Nov And more recently: Sottinen, Tommi ORMS course notes. Pryor, Jennifer; Chinneck, John W , "Faster integer-feasibility in mixed-integer linear programs by branching to force change", Computers and Operations Research 38 8 : , doi :
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Use pricing. Relaxation Relaxation parameter used in the ratio test. If it is zero, the textbook ratio test is used. In the latter case on the first pass of the ratio test basic variables in the case of primal simplex or reduced costs of non-basic variables in the case of dual simplex are allowed to slightly violate their bounds, but not more than the feasibility tolerance or the dual feasibility tolerance thus, the parameter is a percentage of the feasibility or dual feasibility tolerances.
Feasibility tolerance Relative tolerance used to check if the current basic solution is primal feasible. Dual feasibility tolerance Absolute tolerance used to check if the current basic solution is dual feasible. Pivot tolerance Relative tolerance used to choose eligible pivotal elements of the simplex table.
Solution rounding Sets which solution rounding option. Objective lower limit Lower limit of the objective function. If on the phase II the objective function reaches this limit and continues decreasing, the solver stops the search. Used in the dual simplex only. Objective upper limit Upper limit of the objective function. If on the phase II the objective function reaches this limit and continues increasing, the solver stops the search.
Iteration limit Simplex iterations limit. If this value is positive, it is decreased by one each time when one simplex iteration has been performed, and reaching zero value signals the solver to stop the search.
Negative value means no iterations limit. Time limit Searching time limit, in seconds. If this value is positive, it is decreased each time when one simplex iteration has been performed by the amount of time spent for the iteration, and reaching zero value signals the solver to stop the search. Negative value means no time limit. Log output frequency Output frequency, in iterations.
This parameter specifies how frequently the solver sends information about the solution to the log output. Log output delay Output delay, in seconds.
This parameter specifies how long the solver should delay sending information about the solution to the output device. Non-positive value means no delay. Variable Selection The variable selection option is used to set the rule for selecting the branching variable. First Variable 0 Branch on the first variable. Last Variable 1 Branch on the last variable.
Heuristic Branching 2 Branch using a heuristic by Driebeck and Tomlin. Backtracking method The node selection option is used to set the rule for selecting the next node to process when backtracking. Depth first 0 Depth first search chooses the most recently created node.
Breadth first 1 Breadth first search chooses the node with the best LP relaxed objective value. Projection Heuristic 2 Backtracking using the best projection heuristic. Integral feasible tolerance Absolute tolerance used to check if the current basic solution is integer feasible. Relative objective gap Relative tolerance used to check if the value of the objective function is not better than in the best known integer feasible solution.
Write comment cards Is a boolean option that writes out several comment cards, which contains some information about the problem in MPS format. Otherwise the routine writes no comment cards. Relaying objective This parameter tells how to relay the objective function row. No output 0 Never output objective function row.
Always output 1 Always output objective function row. No free rows 2 Output objective function row if the problem has no free rows. Use original names A flag that sets whether to uses the original symbolic names of rows and columns. Otherwise uses plain names using ordinal numbers of rows and columns. Otherwise the routine outputs all columns. Binarize discrete variables Boolean option that replaces general integer variables by binary ones.
Cutting plane settings Is a bitwise operator that determines whether specifc cutting planes are added to the MIP problem. Mix Cover Cuts 1 Add mixed cover cuts to the model. Clique Cuts 2 Add clique cuts to the model. Gomory Cuts 4 Add gomory mixed integer cuts. All Cuts
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To make sure that the GLPK distribution tarball you have downloaded is intact you need to download the corresponding. For more information on customizing the embed code, read Embedding Snippets. There are several interfaces for Python: Jacson Querubin May 29, at Shared items An error has occurred; the feed is probably down. Email required Address never made public. If the relative mip gap for currently known best integer feasible solution falls below this tolerance, the solver terminates the search.
GLPK REFERENCE MANUAL PDF
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