lemon/dim2.h
author deba
Fri, 08 Sep 2006 08:55:07 +0000
changeset 2212 0ad3835449f8
parent 2207 75a29ac69c19
child 2214 a886e48e0d91
permissions -rw-r--r--
Some small improvments

size() and subscription operators
compatibility with higher dimensions
     1 /* -*- C++ -*-
     2  *
     3  * This file is a part of LEMON, a generic C++ optimization library
     4  *
     5  * Copyright (C) 2003-2006
     6  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     7  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     8  *
     9  * Permission to use, modify and distribute this software is granted
    10  * provided that this copyright notice appears in all copies. For
    11  * precise terms see the accompanying LICENSE file.
    12  *
    13  * This software is provided "AS IS" with no warranty of any kind,
    14  * express or implied, and with no claim as to its suitability for any
    15  * purpose.
    16  *
    17  */
    18 
    19 #ifndef LEMON_DIM2_H
    20 #define LEMON_DIM2_H
    21 
    22 #include <iostream>
    23 #include <lemon/bits/utility.h>
    24 
    25 ///\ingroup misc
    26 ///\file
    27 ///\brief A simple two dimensional vector and a bounding box implementation 
    28 ///
    29 /// The class \ref lemon::dim2::Point "dim2::Point" implements
    30 ///a two dimensional vector with the usual
    31 /// operations.
    32 ///
    33 /// The class \ref lemon::dim2::BoundingBox "dim2::BoundingBox"
    34 /// can be used to determine
    35 /// the rectangular bounding box of a set of
    36 /// \ref lemon::dim2::Point "dim2::Point"'s.
    37 ///
    38 ///\author Attila Bernath
    39 
    40 
    41 namespace lemon {
    42 
    43   ///Tools for handling two dimensional coordinates
    44 
    45   ///This namespace is a storage of several
    46   ///tools for handling two dimensional coordinates
    47   namespace dim2 {
    48 
    49   /// \addtogroup misc
    50   /// @{
    51 
    52   /// A simple two dimensional vector (plainvector) implementation
    53 
    54   /// A simple two dimensional vector (plainvector) implementation
    55   ///with the usual vector
    56   /// operators.
    57   ///
    58   template<typename T>
    59     class Point {
    60 
    61     public:
    62 
    63       typedef T Value;
    64 
    65       ///First co-ordinate
    66       T x;
    67       ///Second co-ordinate
    68       T y;     
    69       
    70       ///Default constructor
    71       Point() {}
    72 
    73       ///Construct an instance from coordinates
    74       Point(T a, T b) : x(a), y(b) { }
    75 
    76       ///Size of vector
    77       int size() const { return 2; }
    78 
    79       ///Subscripting operator
    80       T& operator[](int idx) { return idx == 0 ? x : y; }
    81 
    82       ///Const subscripting operator
    83       const T& operator[](int idx) const { return idx == 0 ? x : y; }
    84 
    85       ///Conversion constructor
    86       template<class TT> Point(const Point<TT> &p) : x(p.x), y(p.y) {}
    87 
    88       ///Give back the square of the norm of the vector
    89       T normSquare() const {
    90         return x*x+y*y;
    91       }
    92   
    93       ///Increment the left hand side by u
    94       Point<T>& operator +=(const Point<T>& u) {
    95         x += u.x;
    96         y += u.y;
    97         return *this;
    98       }
    99   
   100       ///Decrement the left hand side by u
   101       Point<T>& operator -=(const Point<T>& u) {
   102         x -= u.x;
   103         y -= u.y;
   104         return *this;
   105       }
   106 
   107       ///Multiply the left hand side with a scalar
   108       Point<T>& operator *=(const T &u) {
   109         x *= u;
   110         y *= u;
   111         return *this;
   112       }
   113 
   114       ///Divide the left hand side by a scalar
   115       Point<T>& operator /=(const T &u) {
   116         x /= u;
   117         y /= u;
   118         return *this;
   119       }
   120   
   121       ///Return the scalar product of two vectors
   122       T operator *(const Point<T>& u) const {
   123         return x*u.x+y*u.y;
   124       }
   125   
   126       ///Return the sum of two vectors
   127       Point<T> operator+(const Point<T> &u) const {
   128         Point<T> b=*this;
   129         return b+=u;
   130       }
   131 
   132       ///Return the neg of the vectors
   133       Point<T> operator-() const {
   134         Point<T> b=*this;
   135         b.x=-b.x; b.y=-b.y;
   136         return b;
   137       }
   138 
   139       ///Return the difference of two vectors
   140       Point<T> operator-(const Point<T> &u) const {
   141         Point<T> b=*this;
   142         return b-=u;
   143       }
   144 
   145       ///Return a vector multiplied by a scalar
   146       Point<T> operator*(const T &u) const {
   147         Point<T> b=*this;
   148         return b*=u;
   149       }
   150 
   151       ///Return a vector divided by a scalar
   152       Point<T> operator/(const T &u) const {
   153         Point<T> b=*this;
   154         return b/=u;
   155       }
   156 
   157       ///Test equality
   158       bool operator==(const Point<T> &u) const {
   159         return (x==u.x) && (y==u.y);
   160       }
   161 
   162       ///Test inequality
   163       bool operator!=(Point u) const {
   164         return  (x!=u.x) || (y!=u.y);
   165       }
   166 
   167     };
   168 
   169   ///Return an Point 
   170 
   171   ///Return an Point
   172   ///\relates Point
   173   template <typename T>
   174   inline Point<T> makePoint(const T& x, const T& y) {
   175     return Point<T>(x, y);
   176   }
   177 
   178   ///Return a vector multiplied by a scalar
   179 
   180   ///Return a vector multiplied by a scalar
   181   ///\relates Point
   182   template<typename T> Point<T> operator*(const T &u,const Point<T> &x) {
   183     return x*u;
   184   }
   185 
   186   ///Read a plainvector from a stream
   187 
   188   ///Read a plainvector from a stream
   189   ///\relates Point
   190   ///
   191   template<typename T>
   192   inline std::istream& operator>>(std::istream &is, Point<T> &z) {
   193     char c;
   194     if (is >> c) {
   195       if (c != '(') is.putback(c);
   196     } else {
   197       is.clear();
   198     }
   199     if (!(is >> z.x)) return is;
   200     if (is >> c) {
   201       if (c != ',') is.putback(c);
   202     } else {
   203       is.clear();
   204     }
   205     if (!(is >> z.y)) return is;
   206     if (is >> c) {
   207       if (c != ')') is.putback(c);
   208     } else {
   209       is.clear();
   210     }
   211     return is;
   212   }
   213 
   214   ///Write a plainvector to a stream
   215 
   216   ///Write a plainvector to a stream
   217   ///\relates Point
   218   ///
   219   template<typename T>
   220   inline std::ostream& operator<<(std::ostream &os, const Point<T>& z)
   221   {
   222     os << "(" << z.x << ", " << z.y << ")";
   223     return os;
   224   }
   225 
   226   ///Rotate by 90 degrees
   227 
   228   ///Returns its parameter rotated by 90 degrees in positive direction.
   229   ///\relates Point
   230   ///
   231   template<typename T>
   232   inline Point<T> rot90(const Point<T> &z)
   233   {
   234     return Point<T>(-z.y,z.x);
   235   }
   236 
   237   ///Rotate by 180 degrees
   238 
   239   ///Returns its parameter rotated by 180 degrees.
   240   ///\relates Point
   241   ///
   242   template<typename T>
   243   inline Point<T> rot180(const Point<T> &z)
   244   {
   245     return Point<T>(-z.x,-z.y);
   246   }
   247 
   248   ///Rotate by 270 degrees
   249 
   250   ///Returns its parameter rotated by 90 degrees in negative direction.
   251   ///\relates Point
   252   ///
   253   template<typename T>
   254   inline Point<T> rot270(const Point<T> &z)
   255   {
   256     return Point<T>(z.y,-z.x);
   257   }
   258 
   259   
   260 
   261   /// A class to calculate or store the bounding box of plainvectors.
   262 
   263   /// A class to calculate or store the bounding box of plainvectors.
   264   ///
   265   ///\author Attila Bernath
   266   template<typename T>
   267     class BoundingBox {
   268       Point<T> bottom_left, top_right;
   269       bool _empty;
   270     public:
   271       
   272       ///Default constructor: creates an empty bounding box
   273       BoundingBox() { _empty = true; }
   274 
   275       ///Construct an instance from one point
   276       BoundingBox(Point<T> a) { bottom_left=top_right=a; _empty = false; }
   277 
   278       ///Were any points added?
   279       bool empty() const {
   280         return _empty;
   281       }
   282 
   283       ///Make the BoundingBox empty
   284       void clear() {
   285         _empty=1;
   286       }
   287 
   288       ///Give back the bottom left corner
   289 
   290       ///Give back the bottom left corner.
   291       ///If the bounding box is empty, then the return value is not defined.
   292       Point<T> bottomLeft() const {
   293         return bottom_left;
   294       }
   295 
   296       ///Set the bottom left corner
   297 
   298       ///Set the bottom left corner.
   299       ///It should only bee used for non-empty box.
   300       void bottomLeft(Point<T> p) {
   301 	bottom_left = p;
   302       }
   303 
   304       ///Give back the top right corner
   305 
   306       ///Give back the top right corner.
   307       ///If the bounding box is empty, then the return value is not defined.
   308       Point<T> topRight() const {
   309         return top_right;
   310       }
   311 
   312       ///Set the top right corner
   313 
   314       ///Set the top right corner.
   315       ///It should only bee used for non-empty box.
   316       void topRight(Point<T> p) {
   317 	top_right = p;
   318       }
   319 
   320       ///Give back the bottom right corner
   321 
   322       ///Give back the bottom right corner.
   323       ///If the bounding box is empty, then the return value is not defined.
   324       Point<T> bottomRight() const {
   325         return Point<T>(top_right.x,bottom_left.y);
   326       }
   327 
   328       ///Set the bottom right corner
   329 
   330       ///Set the bottom right corner.
   331       ///It should only bee used for non-empty box.
   332       void bottomRight(Point<T> p) {
   333 	top_right.x = p.x;
   334 	bottom_left.y = p.y;
   335       }
   336  
   337       ///Give back the top left corner
   338 
   339       ///Give back the top left corner.
   340       ///If the bounding box is empty, then the return value is not defined.
   341       Point<T> topLeft() const {
   342         return Point<T>(bottom_left.x,top_right.y);
   343       }
   344 
   345       ///Set the top left corner
   346 
   347       ///Set the top left corner.
   348       ///It should only bee used for non-empty box.
   349       void topLeft(Point<T> p) {
   350 	top_right.y = p.y;
   351 	bottom_left.x = p.x;
   352       }
   353 
   354       ///Give back the bottom of the box
   355 
   356       ///Give back the bottom of the box.
   357       ///If the bounding box is empty, then the return value is not defined.
   358       T bottom() const {
   359         return bottom_left.y;
   360       }
   361 
   362       ///Set the bottom of the box
   363 
   364       ///Set the bottom of the box.
   365       ///It should only bee used for non-empty box.
   366       void bottom(T t) {
   367 	bottom_left.y = t;
   368       }
   369 
   370       ///Give back the top of the box
   371 
   372       ///Give back the top of the box.
   373       ///If the bounding box is empty, then the return value is not defined.
   374       T top() const {
   375         return top_right.y;
   376       }
   377 
   378       ///Set the top of the box
   379 
   380       ///Set the top of the box.
   381       ///It should only bee used for non-empty box.
   382       void top(T t) {
   383 	top_right.y = t;
   384       }
   385 
   386       ///Give back the left side of the box
   387 
   388       ///Give back the left side of the box.
   389       ///If the bounding box is empty, then the return value is not defined.
   390       T left() const {
   391         return bottom_left.x;
   392       }
   393  
   394       ///Set the left side of the box
   395 
   396       ///Set the left side of the box.
   397       ///It should only bee used for non-empty box
   398       void left(T t) {
   399 	bottom_left.x = t;
   400       }
   401 
   402       /// Give back the right side of the box
   403 
   404       /// Give back the right side of the box.
   405       ///If the bounding box is empty, then the return value is not defined.
   406       T right() const {
   407         return top_right.x;
   408       }
   409 
   410       ///Set the right side of the box
   411 
   412       ///Set the right side of the box.
   413       ///It should only bee used for non-empty box
   414       void right(T t) {
   415 	top_right.x = t;
   416       }
   417 
   418       ///Give back the height of the box
   419 
   420       ///Give back the height of the box.
   421       ///If the bounding box is empty, then the return value is not defined.
   422       T height() const {
   423         return top_right.y-bottom_left.y;
   424       }
   425 
   426       ///Give back the width of the box
   427 
   428       ///Give back the width of the box.
   429       ///If the bounding box is empty, then the return value is not defined.
   430       T width() const {
   431         return top_right.x-bottom_left.x;
   432       }
   433 
   434       ///Checks whether a point is inside a bounding box
   435       bool inside(const Point<T>& u){
   436         if (_empty)
   437           return false;
   438         else{
   439           return ((u.x-bottom_left.x)*(top_right.x-u.x) >= 0 &&
   440               (u.y-bottom_left.y)*(top_right.y-u.y) >= 0 );
   441         }
   442       }
   443   
   444       ///Increments a bounding box with a point
   445       BoundingBox& add(const Point<T>& u){
   446         if (_empty){
   447           bottom_left=top_right=u;
   448           _empty = false;
   449         }
   450         else{
   451           if (bottom_left.x > u.x) bottom_left.x = u.x;
   452           if (bottom_left.y > u.y) bottom_left.y = u.y;
   453           if (top_right.x < u.x) top_right.x = u.x;
   454           if (top_right.y < u.y) top_right.y = u.y;
   455         }
   456         return *this;
   457       }
   458   
   459 //       ///Sums a bounding box and a point
   460 //       BoundingBox operator +(const Point<T>& u){
   461 //         BoundingBox b = *this;
   462 //         return b += u;
   463 //       }
   464 
   465       ///Increments a bounding box with another bounding box
   466       BoundingBox& add(const BoundingBox &u){
   467         if ( !u.empty() ){
   468           this->add(u.bottomLeft());
   469 	  this->add(u.topRight());
   470         }
   471         return *this;
   472       }
   473   
   474       ///Sums two bounding boxes
   475       BoundingBox operator +(const BoundingBox& u){
   476         BoundingBox b = *this;
   477         return b.add(u);
   478       }
   479 
   480 
   481       ///Intersection of two bounding boxes
   482       BoundingBox operator &(const BoundingBox& u){
   483         BoundingBox b;
   484 	b.bottom_left.x=std::max(this->bottom_left.x,u.bottom_left.x);
   485 	b.bottom_left.y=std::max(this->bottom_left.y,u.bottom_left.y);
   486 	b.top_right.x=std::min(this->top_right.x,u.top_right.x);
   487 	b.top_right.y=std::min(this->top_right.y,u.top_right.y);
   488 	b._empty = this->_empty || u._empty ||
   489 	  b.bottom_left.x>top_right.x && b.bottom_left.y>top_right.y;
   490         return b;
   491       }
   492 
   493     };//class Boundingbox
   494 
   495 
   496   ///Map of x-coordinates of a dim2::Point<>-map
   497 
   498   ///\ingroup maps
   499   ///
   500   template<class M>
   501   class XMap 
   502   {
   503     M& _map;
   504   public:
   505 
   506     typedef typename M::Value::Value Value;
   507     typedef typename M::Key Key;
   508     ///\e
   509     XMap(M& map) : _map(map) {}
   510     Value operator[](Key k) const {return _map[k].x;}
   511     void set(Key k,Value v) {_map.set(k,typename M::Value(v,_map[k].y));}
   512   };
   513     
   514   ///Returns an \ref XMap class
   515 
   516   ///This function just returns an \ref XMap class.
   517   ///
   518   ///\ingroup maps
   519   ///\relates XMap
   520   template<class M> 
   521   inline XMap<M> xMap(M &m) 
   522   {
   523     return XMap<M>(m);
   524   }
   525 
   526   template<class M> 
   527   inline XMap<M> xMap(const M &m) 
   528   {
   529     return XMap<M>(m);
   530   }
   531 
   532   ///Constant (read only) version of \ref XMap
   533 
   534   ///\ingroup maps
   535   ///
   536   template<class M>
   537   class ConstXMap 
   538   {
   539     const M& _map;
   540   public:
   541 
   542     typedef typename M::Value::Value Value;
   543     typedef typename M::Key Key;
   544     ///\e
   545     ConstXMap(const M &map) : _map(map) {}
   546     Value operator[](Key k) const {return _map[k].x;}
   547   };
   548     
   549   ///Returns a \ref ConstXMap class
   550 
   551   ///This function just returns an \ref ConstXMap class.
   552   ///
   553   ///\ingroup maps
   554   ///\relates ConstXMap
   555   template<class M> 
   556   inline ConstXMap<M> xMap(const M &m) 
   557   {
   558     return ConstXMap<M>(m);
   559   }
   560 
   561   ///Map of y-coordinates of a dim2::Point<>-map
   562     
   563   ///\ingroup maps
   564   ///
   565   template<class M>
   566   class YMap 
   567   {
   568     M& _map;
   569   public:
   570 
   571     typedef typename M::Value::Value Value;
   572     typedef typename M::Key Key;
   573     ///\e
   574     YMap(M& map) : _map(map) {}
   575     Value operator[](Key k) const {return _map[k].y;}
   576     void set(Key k,Value v) {_map.set(k,typename M::Value(_map[k].x,v));}
   577   };
   578 
   579   ///Returns an \ref YMap class
   580 
   581   ///This function just returns an \ref YMap class.
   582   ///
   583   ///\ingroup maps
   584   ///\relates YMap
   585   template<class M> 
   586   inline YMap<M> yMap(M &m) 
   587   {
   588     return YMap<M>(m);
   589   }
   590 
   591   template<class M> 
   592   inline YMap<M> yMap(const M &m) 
   593   {
   594     return YMap<M>(m);
   595   }
   596 
   597   ///Constant (read only) version of \ref YMap
   598 
   599   ///\ingroup maps
   600   ///
   601   template<class M>
   602   class ConstYMap 
   603   {
   604     const M& _map;
   605   public:
   606 
   607     typedef typename M::Value::Value Value;
   608     typedef typename M::Key Key;
   609     ///\e
   610     ConstYMap(const M &map) : _map(map) {}
   611     Value operator[](Key k) const {return _map[k].y;}
   612   };
   613     
   614   ///Returns a \ref ConstYMap class
   615 
   616   ///This function just returns an \ref ConstYMap class.
   617   ///
   618   ///\ingroup maps
   619   ///\relates ConstYMap
   620   template<class M> 
   621   inline ConstYMap<M> yMap(const M &m) 
   622   {
   623     return ConstYMap<M>(m);
   624   }
   625 
   626 
   627   ///Map of the \ref Point::normSquare() "normSquare()" of an \ref Point "Point"-map
   628 
   629   ///Map of the \ref Point::normSquare() "normSquare()" of an \ref Point "Point"-map
   630   ///\ingroup maps
   631   ///
   632   template<class M>
   633   class NormSquareMap 
   634   {
   635     const M& _map;
   636   public:
   637 
   638     typedef typename M::Value::Value Value;
   639     typedef typename M::Key Key;
   640     ///\e
   641     NormSquareMap(const M &map) : _map(map) {}
   642     Value operator[](Key k) const {return _map[k].normSquare();}
   643   };
   644     
   645   ///Returns a \ref NormSquareMap class
   646 
   647   ///This function just returns an \ref NormSquareMap class.
   648   ///
   649   ///\ingroup maps
   650   ///\relates NormSquareMap
   651   template<class M> 
   652   inline NormSquareMap<M> normSquareMap(const M &m) 
   653   {
   654     return NormSquareMap<M>(m);
   655   }
   656 
   657   /// @}
   658 
   659   } //namespce dim2
   660   
   661 } //namespace lemon
   662 
   663 #endif //LEMON_DIM2_H