CPLEX Parameter Table - Revision history

WikiSysop: /* Table: CPLEX Parameters Overview */

2021-09-23T14:18:42Z

Table: CPLEX Parameters Overview

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	2 Reduce all potential coefficients		2 Reduce all potential coefficients

	3 Reduce aggressively with tilting		3 Reduce aggressively with ''tilting''

	Default: -1		Default: -1
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	Determines how coefficient reduction is used. Coefficient reduction improves the objective value of the initial (and subsequent) LP relaxations solved during branch & cut by reducing the number of non-integral vertices.		Determines how coefficient reduction is used. Coefficient reduction improves the objective value of the initial (and subsequent) LP relaxations solved during branch & cut by reducing the number of non-integral vertices.

			The most aggressive setting (3) applies a method called ''tilting''. Tilting can cut off additional fractional solutions in some models, potentially yielding better progress in both the best node and best integer solution.
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WikiSysop: /* Table: CPLEX Parameters Overview */ COEREDIND

2021-09-23T12:27:35Z

Table: CPLEX Parameters Overview: COEREDIND

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	\|cpxControl.COEREDIND\|\|0 Do not use coefficient reduction		\|cpxControl.COEREDIND\|\|-1 Let CPLEX decide

			0 Do not use coefficient reduction

	1 Reduce only to integral coefficients		1 Reduce only to integral coefficients
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	2 Reduce all potential coefficients		2 Reduce all potential coefficients

			3 Reduce aggressively with tilting

			Default: -1
	Default: 2

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	\|colspan="2"\|'''Description: '''Coefficient reduction setting.		\|colspan="2"\|'''Description: '''Coefficient reduction setting.

	Determines how coefficient reduction is used. Coefficient reduction improves the objective value of the initial		Determines how coefficient reduction is used. Coefficient reduction improves the objective value of the initial (and subsequent) LP relaxations solved during branch & cut by reducing the number of non-integral vertices.

	(and subsequent) LP relaxations solved during branch & cut by reducing the number of non-integral vertices.
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WikiSysop: /* Table: CPLEX Parameters Overview */

2021-09-09T13:14:05Z

Table: CPLEX Parameters Overview

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	\|colspan="2"\|'''Description: '''~~Bound~~ strengthening ~~indicator~~.		\|colspan="2"\|'''Description: '''Decides whether to apply bound strengthening in mixed integer programs.

	~~Used when solving mixed integer programs.~~ Bound strengthening tightens the bounds on variables, perhaps to the point where the variable can be fixed and thus removed from consideration during branch & cut. This reduction is usually beneficial, but occasionally, due to its iterative nature, takes a long time.		Bound strengthening tightens the bounds on variables, perhaps to the point where the variable can be fixed and thus removed from consideration during branch & cut. This reduction is usually beneficial, but occasionally, due to its iterative nature, takes a long time.
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WikiSysop: /* Table: CPLEX Parameters Overview */ bbinterval

2021-09-08T09:43:37Z

Table: CPLEX Parameters Overview: bbinterval

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	\|cpxControl.BARQCPEPCOMP\|\|Any positive number ''>= 1E-12''		\|cpxControl.BARQCPEPCOMP\|\|Any positive number ''>= 1E-12''

			Default: ''1E-7''

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	~~Default~~: '~~'1E-7~~''		\|colspan="2"\|'''Description: '''Convergence tolerance for quadratically constrained problems (QCP). For LPs and for QPs (i.e. when all the constraints are linear) see BAREPCOMP.

	~~\|-valign="top"~~		Sets the tolerance on complementarity for convergence. The barrier algorithm terminates with an optimal solution if the relative complementarity is smaller than this value. Changing this tolerance to a smaller value may result in greater numerical precision of the solution, but also increases the chance of a convergence failure in the algorithm and consequently may result in no solution at all. Therefore, caution is advised in deviating from the default setting.

	~~\|colspan="2"\|'''Description: '''Convergence tolerance for QCP problems. That is, for quadratically constrained problems. For~~

	LPs and for QPs (that is, when all the constraints are linear) see BAREPCOMP. Sets the tolerance on complementarity for convergence. The barrier algorithm terminates with an optimal solution if the relative complementarity is smaller than this value. Changing this tolerance to a smaller value may result in greater numerical precision of the solution, but also increases the chance of a convergence failure in the algorithm and consequently may result in no solution at all. Therefore, caution is advised in deviating from the default setting.
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	\|cpxControl.BBINTERVAL\|\|0 ~~Best~~ estimate node ~~always selected or~~, ~~any~~ positive integer		\|cpxControl.BBINTERVAL\|\|0 Always select best estimate node, never select best bound
			1 Always select best bound node
			7 Select best bound node occasionally
			Any positive integer - select best bound node less frequently than best estimate node

			Default: 7

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			\|colspan="2"\|'''Description: '''Sets best bound interval for MIP strategy
			When you set this parameter to best estimate node selection, the best bound interval is the interval at which the best bound node, instead of the best estimate node, is selected from the tree.

	~~Default: 7~~		BBINTERVAL=0 means to never select the best bound node.

	~~\|-valign~~=~~"top"~~		BBINTERVAL=1 means to always select the best bound node, and is thus equivalent to NODESEL=1.

	~~\|colspan="2"\|'''Description: '''MIP strategy bbinterval~~.		Higher values of BBINTERVAL mean that the best bound node will be selected less frequently; experience has shown it to be beneficial to occasionally select the best bound node, and therefore the default value of this parameter is 7.

	When using nodeselect 2, the bbinterval is the interval at which the best bound node, instead of the best estimate node, is selected from the tree. A bbinterval of 0 means to never select the best bound node. A bbinterval of 1 means to always select the best bound node, and is thus equivalent to nodeselect 1. Higher values of bbinterval mean that the best bound node will be selected less frequently; experience has shown it to be beneficial to occasionally select the best bound node, and therefore the default bbinterval is 7.
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WikiSysop: /* Table: CPLEX Parameters Overview */

2021-09-08T09:09:15Z

Table: CPLEX Parameters Overview

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	Default: 0 ~~values~~		Default: 0

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	Sets the algorithm to be used to permute the rows of the constraint matrix in order to reduce fill in the Cholesky factor.		Sets the algorithm to be used to permute the rows of the constraint matrix in order to reduce fill in the Cholesky factor.


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	\|cpxControl.BARQCPEPCOMP\|\|Any positive number ''= ~~''10''~~-''12		\|cpxControl.BARQCPEPCOMP\|\|Any positive number ''>= 1E-12''



	Default: 10''-''6		Default: ''1E-7''

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WikiSysop: /* Table: CPLEX Parameters Overview */

2021-09-06T13:33:24Z

Table: CPLEX Parameters Overview

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	Default: ~~1020~~		Default: 1.0E20

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WikiSysop: /* Table: CPLEX Parameters Overview */

2021-09-06T13:32:03Z

Table: CPLEX Parameters Overview

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	\|cpxControl.BAREPCOMP\|\|Any positive number ''= ~~''10''~~-''12		\|cpxControl.BAREPCOMP\|\|Any positive number ''>= 1.0E-12''



	Default: 10''-''8		Default: ''1.0E-8''

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	Default: ~~108~~		Default: 1.0E12

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WikiSysop: /* Table: CPLEX Parameters Overview */

2021-09-06T10:07:19Z

Table: CPLEX Parameters Overview

← Older revision		Revision as of 06:07, 6 September 2021
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	\|colspan="2"\|'''Description: '''Barrier column nonzeros.		\|colspan="2"\|'''Description: '''Barrier column nonzeros.

	Used in the recognition of dense columns. If columns in the presolved and aggregated problem exist with more entries than this value, such columns are considered dense and are treated specially by the CPLEX Barrier Optimizer to reduce their effect~~. If the problem contains fewer than 400 rows, dense column handling is NOT initiated~~.		Used in the recognition of dense columns. If columns in the presolved and aggregated problem exist with more entries than this value, such columns are considered dense and are treated specially by the CPLEX Barrier Optimizer to reduce their effect.
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WikiSysop: /* Table: CPLEX Parameters Overview */

2021-03-08T13:01:46Z

Table: CPLEX Parameters Overview

← Older revision		Revision as of 09:01, 8 March 2021
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	\|colspan="2"\|'''Description: '''Absolute mipgap tolerance.		\|colspan="2"\|'''Description: '''Absolute mipgap tolerance.

	Sets an absolute tolerance on the gap between the best integer objective and the objective of the best node remaining. When this difference falls below the value of the ~~ABSMIPGAP~~ parameter, the mixed integer optimization is stopped.		Sets an absolute tolerance on the gap between the best integer objective and the objective of the best node remaining. When this difference falls below the value of the EPGAP parameter, the mixed integer optimization is stopped.
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Ango: /* Table: CPLEX Parameters Overview */ DETTILIM

2020-05-20T08:27:08Z

Table: CPLEX Parameters Overview: DETTILIM

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 Determines whether to activate the "dependency checker". If on, the dependency checker searches for dependent rows during preprocessing. If off, dependent rows are not identified.
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 |cpxControl.TILIM||Any non-negative number