comparer.h File Reference

Declarations for Comparer objects. More...

Go to the source code of this file.

Classes
class	ogdf::StdComparer< E >
	Standard comparer (valid as a static comparer). More...
class	ogdf::StdComparer< int >
class	ogdf::StdComparer< float >
class	ogdf::StdComparer< double >
class	ogdf::StdComparer< bool >
	Generates a specialization of the standard static comparer for booleans. More...
class	ogdf::TargetComparer< CONTENTTYPE, STATICCONTENTCOMPARER >
	A static comparer which compares the target of pointers ("content"), instead of the pointer's adresses. More...
class	ogdf::VComparer< E >
	Abstract base class for comparer classes. More...
Namespaces
namespace	ogdf
	The namespace for all OGDF objects.
Defines
#define	OGDF_COMPARER_H
#define	OGDF_STD_COMPARER(type)
	Generates a specialization of the standard static comparer for type based on compare operators.
#define	OGDF_AUGMENT_COMPARER(type)
	Add this macro to your class to turn it into a full comparer.
#define	OGDF_AUGMENT_STATICCOMPARER(type)
	Add this macro to your class to turn it into a full static comparer.

---

Detailed Description

Declarations for Comparer objects.

Author:

Markus Chimani, Carsten Gutwenger

License:

This file is part of the Open Graph Drawing Framework (OGDF).

Copyright (C). All rights reserved. See README.txt in the root directory of the OGDF installation for details.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License Version 2 or 3 as published by the Free Software Foundation; see the file LICENSE.txt included in the packaging of this file for details.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

See also:

http://www.gnu.org/copyleft/gpl.html

Definition in file comparer.h.

---

Define Documentation

#define OGDF_AUGMENT_COMPARER

(

type

)

Value:

public: \
    bool less(const type &x, const type &y) const { return compare(x,y) < 0; } \
    bool leq(const type &x, const type &y) const { return compare(x,y) <= 0; } \
    bool greater(const type &x, const type &y) const { return compare(x,y) > 0; } \
    bool geq(const type &x, const type &y) const { return compare(x,y) >= 0; } \
    bool equal(const type &x, const type &y) const { return compare(x,y) == 0; }

Add this macro to your class to turn it into a full comparer.

It is assumed that your class has a method "compare(const type &x, const type &y)", which returns 0 if the two elements are equal, a negative value if x is smaller, and a positive value if x is greater.

Note: If the compare function of your class requires no additional data other than the two elements to compare, your should usually use the more general OGDF_AUGMENT_STATICCOMPARER: A static comparer is also always valid as a normal comparer.

Usage in Definition:

 class MyComparer {
 private:
   Oracle oracle;
 public:
   MyComparer(Oracle o) : oracle(o) {}
   int compare(const MyStuff& x1, const MyStuff& x2) const {
      return ... //compare x1 with x2, using oracle
   }
   OGDF_AUGMENT_COMPARER(MyStuff)
 }

Use the Comparer:

 MyStuff a=...;
 MyStuff b=...;
 Oracle or;
 MyComparer comp(or);
 if( comp.less(a,b) )
   ... // do something
 ...
 Array<MyStuff> ay(10);
 ... // fill array
 ay.quicksort(comp); // sort the array using the MyComparer comp

Definition at line 170 of file comparer.h.

#define OGDF_AUGMENT_STATICCOMPARER

(

type

)

Value:

public: \
    static bool less(const type &x, const type &y) { return compare(x,y) < 0; } \
    static bool leq(const type &x, const type &y) { return compare(x,y) <= 0; } \
    static bool greater(const type &x, const type &y) { return compare(x,y) > 0; } \
    static bool geq(const type &x, const type &y) { return compare(x,y) >= 0; } \
    static bool equal(const type &x, const type &y) { return compare(x,y) == 0; }

Add this macro to your class to turn it into a full static comparer.

It is assumed that your class has a static method "compare(const type &x, const type &y)", which returns 0 if the two elements are equal, a negative value if x is smaller, and a positive value if x is greater.

Note: You should use this macro instead of OGDF_AUGMENT_COMPARER whenever your compare function requires no additional data stored in the object, other than the two elements to compare. A static comparer is also always valid as a normal comparer.

Usage in Definition:

 class MyComparer {
 public:
    static int comparer(const MyStuff& x1, const MyStuff& x2) {
       return ... //compare x1 with x2
    }
    OGDF_AUGMENT_STATICCOMPARER(MyStuff)
 }

Use the Comparer:

 MyStuff a=...;
 MyStuff b=...;
 MyComparer comp;
 if( MyComparer.less(a,b) ) // use it statically on the class
    ... // do something
 if( comp.less(a,b) ) // use it on the object
    ... // do something
 ...
 Array<MyStuff> ay(10);
 ... // fill array
 ay.quicksort(comp); // sort the array using the MyComparer comp

Definition at line 214 of file comparer.h.

#define OGDF_COMPARER_H

Definition at line 48 of file comparer.h.

#define OGDF_STD_COMPARER

(

type

)

Value:

template<> class StdComparer<type> \
    { \
    public: \
        static bool less   (const type &x, const type &y) { return x <  y; } \
        static bool leq    (const type &x, const type &y) { return x <= y; } \
        static bool greater(const type &x, const type &y) { return x >  y; } \
        static bool geq    (const type &x, const type &y) { return x >= y; } \
        static bool equal  (const type &x, const type &y) { return x == y; } \
    };

Generates a specialization of the standard static comparer for type based on compare operators.

Definition at line 90 of file comparer.h.