SteelMill Class Reference
[Example scripts (models)]

Example: Steel-mill slab design problem More...

List of all members.

Classes
class	SteelMillBranch
	Custom brancher for steel mill slab design. More...
Public Types
enum	{ SYMMETRY_NONE, SYMMETRY_BRANCHING }
	Branching variants. More...
Public Member Functions
	SteelMill (const SteelMillOptions &opt)
	Actual model.
virtual void	print (std::ostream &os) const
	Print solution.
	SteelMill (bool share, SteelMill &s)
	Constructor for cloning s.
virtual Space *	copy (bool share)
	Copy during cloning.
virtual IntVar	cost (void) const
	Return solution cost.
Instance specification
int *	capacities
	Capacities.
int	ncapacities
	Number of capacities.
int	maxcapacity
	Maximum capacity.
int *	loss
	Loss for all sizes.
int	ncolors
	Number of colors.
order_t	orders
	Orders.
unsigned int	norders
	Number of orders.
unsigned int	nslabs
	Number of slabs.
Problem variables
IntVarArray	slab
	Slab assigned to order i.
IntVarArray	slabload
	Load of slab j.
IntVarArray	slabcost
	Cost of slab j.
IntVar	total_cost
	Total cost.

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Detailed Description

Example: Steel-mill slab design problem

This model solves the Steel Mill Slab Design Problem (Problem 38 in CSPLib). The model is from Gargani and Refalo, "An efficient model and strategy for the steel mill slab design problem.", CP 2007, except that a decomposition of the packing constraint is used. The symmetry-breaking search is from Van Hentenryck and Michel, "The Steel Mill Slab Design Problem Revisited", CPAIOR 2008.

The program accepts an optional argument for a data-file containing an instance of the problem. The format for the data-file is the following:

 "number of slab capacities" "sequence of capacities in increasing order"
 "number of colors"
 "number of orders"
 "size order 1" "color of order 1"
 "size order 2" "color of order 2"
 ...
 

Hard instances are available from http://becool.info.ucl.ac.be/steelmillslab.

Definition at line 147 of file steel-mill.cpp.

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Member Enumeration Documentation

anonymous enum

Branching variants.

Enumerator:

SYMMETRY_NONE	Simple symmetry.
SYMMETRY_BRANCHING	Breaking symmetries with symmetry.

Definition at line 173 of file steel-mill.cpp.

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Constructor & Destructor Documentation

SteelMill::SteelMill

(

const SteelMillOptions &

opt

)

[inline]

Actual model.

Definition at line 179 of file steel-mill.cpp.

SteelMill::SteelMill	(	bool	share,
		SteelMill &	s
	)			[inline]

Constructor for cloning s.

Definition at line 289 of file steel-mill.cpp.

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Member Function Documentation

virtual void SteelMill::print

(

std::ostream &

os

)

const [inline, virtual]

Print solution.

Reimplemented from Gecode::Driver::ScriptBase< BaseSpace >.

Definition at line 265 of file steel-mill.cpp.

virtual Space* SteelMill::copy

(

bool

share

)

[inline, virtual]

Copy during cloning.

Definition at line 302 of file steel-mill.cpp.

virtual IntVar SteelMill::cost

(

void

)

const [inline, virtual]

Return solution cost.

Definition at line 306 of file steel-mill.cpp.

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Member Data Documentation

int* SteelMill::capacities [protected]

Capacities.

Definition at line 152 of file steel-mill.cpp.

int SteelMill::ncapacities [protected]

Number of capacities.

Definition at line 153 of file steel-mill.cpp.

int SteelMill::maxcapacity [protected]

Maximum capacity.

Definition at line 154 of file steel-mill.cpp.

int* SteelMill::loss [protected]

Loss for all sizes.

Definition at line 155 of file steel-mill.cpp.

int SteelMill::ncolors [protected]

Number of colors.

Definition at line 156 of file steel-mill.cpp.

order_t SteelMill::orders [protected]

Orders.

Definition at line 157 of file steel-mill.cpp.

unsigned int SteelMill::norders [protected]

Number of orders.

Definition at line 158 of file steel-mill.cpp.

unsigned int SteelMill::nslabs [protected]

Number of slabs.

Definition at line 159 of file steel-mill.cpp.

IntVarArray SteelMill::slab [protected]

Slab assigned to order i.

Definition at line 165 of file steel-mill.cpp.

IntVarArray SteelMill::slabload [protected]

Load of slab j.

Definition at line 165 of file steel-mill.cpp.

IntVarArray SteelMill::slabcost [protected]

Cost of slab j.

Definition at line 165 of file steel-mill.cpp.

IntVar SteelMill::total_cost [protected]

Total cost.

Definition at line 168 of file steel-mill.cpp.

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The documentation for this class was generated from the following file:

• examples/steel-mill.cpp (Revision: 12001)