DescartesFolium Class Reference

Example: Folium of Descartes More...

Public Member Functions
	DescartesFolium (const Options &opt)
	Actual model.
	DescartesFolium (DescartesFolium &p)
	Constructor for cloning p.
virtual Space *	copy (void)
	Copy during cloning.
virtual FloatVar	cost (void) const
	Cost function.
virtual void	print (std::ostream &os) const
	Print solution coordinates.
Public Member Functions inherited from Gecode::Driver::ScriptBase< Driver::ExtractStepOption< FloatMaximizeSpace > >
	ScriptBase (const Options &opt)
	Constructor.
	ScriptBase (ScriptBase &e)
	Constructor used for cloning.
virtual void	compare (const Space &home, std::ostream &os) const
	Compare with s.
Public Member Functions inherited from Gecode::Driver::ExtractStepOption< BaseSpace >
	ExtractStepOption (const Options &opt)
	Constructor that extracts the step value.
	ExtractStepOption (BaseSpace &e)
	Constructor used for cloning.

Protected Attributes
FloatVarArray	f
	The numbers.
double	step
	Minimum distance between two solutions.

Related Symbols
(Note that these are not member symbols.)
int	main (int argc, char *argv[])
	Main-function.

Additional Inherited Members
Static Public Member Functions inherited from Gecode::Driver::ScriptBase< Driver::ExtractStepOption< FloatMaximizeSpace > >
static std::ostream &	select_ostream (const char *sn, std::ofstream &ofs)
	Choose output stream according to sn.
static void	run (const Options &opt, Script *s=nullptr)

Detailed Description

Example: Folium of Descartes

The folium of Descartes is a curve defined by the equation:

\[x^3 + y^3 - 3axy = 0 \]

A technique to solve it, is to write \(y=px\) and solve for \(x\) and \(y\) in terms of \(p\). By setting \(a=1\), it yields to the paramatric equation:

\[x^3 + y^3 - 3xy = 0 \]

\[x=\frac{3p}{1+p^3},\quad y=\frac{3p^2}{1+p^3} \]

The parameter \(p\) is related to the position on the curve and is constrained to get different solutions for \(x\) and \(y\). To get reasonable interval starting sizes, \(p\) and \(y\) are restricted to \([-20;20]\) and \(x\) is restricted to \([-1;2]\).

Definition at line 68 of file descartes-folium.cpp.

Constructor & Destructor Documentation

DescartesFolium() [1/2]

DescartesFolium::DescartesFolium ( const Options & opt )

inline

Actual model.

Definition at line 76 of file descartes-folium.cpp.

DescartesFolium() [2/2]

DescartesFolium::DescartesFolium ( DescartesFolium & p )

inline

Constructor for cloning p.

Definition at line 94 of file descartes-folium.cpp.

Member Function Documentation

copy()

virtual Space * DescartesFolium::copy ( void )

inlinevirtual

Copy during cloning.

Definition at line 99 of file descartes-folium.cpp.

cost()

virtual FloatVar DescartesFolium::cost ( void ) const

inlinevirtual

Cost function.

Definition at line 103 of file descartes-folium.cpp.

print()

virtual void DescartesFolium::print ( std::ostream & os ) const

inlinevirtual

Print solution coordinates.

Reimplemented from Gecode::Driver::ScriptBase< Driver::ExtractStepOption< FloatMaximizeSpace > >.

Definition at line 107 of file descartes-folium.cpp.

Friends And Related Symbol Documentation

main()

int main ( int argc, char * argv[] )

related

Main-function.

Definition at line 117 of file descartes-folium.cpp.

Member Data Documentation

f

FloatVarArray DescartesFolium::f

protected

The numbers.

Definition at line 71 of file descartes-folium.cpp.

step

double DescartesFolium::step

protected

Minimum distance between two solutions.

Definition at line 73 of file descartes-folium.cpp.

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

• examples/descartes-folium.cpp