src/lemon/xy.h
author deba
Wed, 27 Apr 2005 10:37:03 +0000
changeset 1392 b87aa8f0feb8
parent 1391 5b46af577b23
child 1420 e37cca875667
permissions -rw-r--r--
Changed input operator.
     1 /* -*- C++ -*-
     2  * src/lemon/xy.h - Part of LEMON, a generic C++ optimization library
     3  *
     4  * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     5  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     6  *
     7  * Permission to use, modify and distribute this software is granted
     8  * provided that this copyright notice appears in all copies. For
     9  * precise terms see the accompanying LICENSE file.
    10  *
    11  * This software is provided "AS IS" with no warranty of any kind,
    12  * express or implied, and with no claim as to its suitability for any
    13  * purpose.
    14  *
    15  */
    16 
    17 #ifndef LEMON_XY_H
    18 #define LEMON_XY_H
    19 
    20 #include <iostream>
    21 
    22 ///\ingroup misc
    23 ///\file
    24 ///\brief A simple two dimensional vector and a bounding box implementation 
    25 ///
    26 /// The class \ref lemon::xy "xy" implements
    27 ///a two dimensional vector with the usual
    28 /// operations.
    29 ///
    30 /// The class \ref lemon::BoundingBox "BoundingBox" can be used to determine
    31 /// the rectangular bounding box a set of \ref lemon::xy "xy"'s.
    32 ///
    33 ///\author Attila Bernath
    34 
    35 
    36 namespace lemon {
    37 
    38   /// \addtogroup misc
    39   /// @{
    40 
    41   /// A simple two dimensional vector (plainvector) implementation
    42 
    43   /// A simple two dimensional vector (plainvector) implementation
    44   ///with the usual vector
    45   /// operators.
    46   ///
    47   ///\author Attila Bernath
    48   template<typename T>
    49     class xy {
    50 
    51     public:
    52 
    53       typedef T Value;
    54 
    55       T x,y;     
    56       
    57       ///Default constructor
    58       xy() {}
    59 
    60       ///Constructing the instance from coordinates
    61       xy(T a, T b) : x(a), y(b) { }
    62 
    63 
    64       ///Conversion constructor
    65       template<class TT> xy(const xy<TT> &p) : x(p.x), y(p.y) {}
    66 
    67       ///Gives back the square of the norm of the vector
    68       T normSquare() const {
    69 	return x*x+y*y;
    70       }
    71   
    72       ///Increments the left hand side by u
    73       xy<T>& operator +=(const xy<T>& u) {
    74 	x += u.x;
    75 	y += u.y;
    76 	return *this;
    77       }
    78   
    79       ///Decrements the left hand side by u
    80       xy<T>& operator -=(const xy<T>& u) {
    81 	x -= u.x;
    82 	y -= u.y;
    83 	return *this;
    84       }
    85 
    86       ///Multiplying the left hand side with a scalar
    87       xy<T>& operator *=(const T &u) {
    88 	x *= u;
    89 	y *= u;
    90 	return *this;
    91       }
    92 
    93       ///Dividing the left hand side by a scalar
    94       xy<T>& operator /=(const T &u) {
    95 	x /= u;
    96 	y /= u;
    97 	return *this;
    98       }
    99   
   100       ///Returns the scalar product of two vectors
   101       T operator *(const xy<T>& u) const {
   102 	return x*u.x+y*u.y;
   103       }
   104   
   105       ///Returns the sum of two vectors
   106       xy<T> operator+(const xy<T> &u) const {
   107 	xy<T> b=*this;
   108 	return b+=u;
   109       }
   110 
   111       ///Returns the neg of the vectors
   112       xy<T> operator-() const {
   113 	xy<T> b=*this;
   114 	b.x=-b.x; b.y=-b.y;
   115 	return b;
   116       }
   117 
   118       ///Returns the difference of two vectors
   119       xy<T> operator-(const xy<T> &u) const {
   120 	xy<T> b=*this;
   121 	return b-=u;
   122       }
   123 
   124       ///Returns a vector multiplied by a scalar
   125       xy<T> operator*(const T &u) const {
   126 	xy<T> b=*this;
   127 	return b*=u;
   128       }
   129 
   130       ///Returns a vector divided by a scalar
   131       xy<T> operator/(const T &u) const {
   132 	xy<T> b=*this;
   133 	return b/=u;
   134       }
   135 
   136       ///Testing equality
   137       bool operator==(const xy<T> &u) const {
   138 	return (x==u.x) && (y==u.y);
   139       }
   140 
   141       ///Testing inequality
   142       bool operator!=(xy u) const {
   143 	return  (x!=u.x) || (y!=u.y);
   144       }
   145 
   146     };
   147 
   148   ///Returns a vector multiplied by a scalar
   149 
   150   ///Returns a vector multiplied by a scalar
   151   ///\relates xy
   152   template<typename T> xy<T> operator*(const T &u,const xy<T> &x) {
   153     return x*u;
   154   }
   155 
   156   ///Read a plainvector from a stream
   157 
   158   ///Read a plainvector from a stream
   159   ///\relates xy
   160   ///
   161   template<typename T>
   162   inline std::istream& operator>>(std::istream &is, xy<T> &z) {
   163     char c;
   164     if (is >> c) {
   165       if (c != '(') is.putback(c);
   166     } else {
   167       is.clear();
   168     }
   169     if (!(is >> z.x)) return is;
   170     if (is >> c) {
   171       if (c != ',') is.putback(c);
   172     } else {
   173       is.clear();
   174     }
   175     if (!(is >> z.y)) return is;
   176     if (is >> c) {
   177       if (c != ')') is.putback(c);
   178     } else {
   179       is.clear();
   180     }
   181     return is;
   182   }
   183 
   184   ///Write a plainvector to a stream
   185 
   186   ///Write a plainvector to a stream
   187   ///\relates xy
   188   ///
   189   template<typename T>
   190   inline std::ostream& operator<<(std::ostream &os, const xy<T>& z)
   191   {
   192     os << "(" << z.x << ", " << z.y << ")";
   193     return os;
   194   }
   195 
   196   ///Rotate by 90 degrees
   197 
   198   ///Returns its parameter rotated by 90 degrees in positive direction.
   199   ///\relates xy
   200   ///
   201   template<typename T>
   202   inline xy<T> rot90(const xy<T> &z)
   203   {
   204     return xy<T>(-z.y,z.x);
   205   }
   206 
   207   ///Rotate by 270 degrees
   208 
   209   ///Returns its parameter rotated by 90 degrees in negative direction.
   210   ///\relates xy
   211   ///
   212   template<typename T>
   213   inline xy<T> rot270(const xy<T> &z)
   214   {
   215     return xy<T>(z.y,-z.x);
   216   }
   217 
   218   
   219 
   220   /// A class to calculate or store the bounding box of plainvectors.
   221 
   222   /// A class to calculate or store the bounding box of plainvectors.
   223   ///
   224   ///\author Attila Bernath
   225   template<typename T>
   226     class BoundingBox {
   227       xy<T> bottom_left, top_right;
   228       bool _empty;
   229     public:
   230       
   231       ///Default constructor: an empty bounding box
   232       BoundingBox() { _empty = true; }
   233 
   234       ///Constructing the instance from one point
   235       BoundingBox(xy<T> a) { bottom_left=top_right=a; _empty = false; }
   236 
   237       ///Is there any point added
   238       bool empty() const {
   239 	return _empty;
   240       }
   241 
   242       ///Makes the BoundingBox empty
   243       void clear() {
   244 	_empty=1;
   245       }
   246 
   247       ///Gives back the bottom left corner (if the bounding box is empty, then the return value is not defined) 
   248       xy<T> bottomLeft() const {
   249 	return bottom_left;
   250       }
   251 
   252       ///Gives back the top right corner (if the bounding box is empty, then the return value is not defined) 
   253       xy<T> topRight() const {
   254 	return top_right;
   255       }
   256 
   257       ///Gives back the bottom right corner (if the bounding box is empty, then the return value is not defined) 
   258       xy<T> bottomRight() const {
   259 	return xy<T>(top_right.x,bottom_left.y);
   260       }
   261 
   262       ///Gives back the top left corner (if the bounding box is empty, then the return value is not defined) 
   263       xy<T> topLeft() const {
   264 	return xy<T>(bottom_left.x,top_right.y);
   265       }
   266 
   267       ///Gives back the bottom of the box (if the bounding box is empty, then the return value is not defined) 
   268       T bottom() const {
   269 	return bottom_left.y;
   270       }
   271 
   272       ///Gives back the top of the box (if the bounding box is empty, then the return value is not defined) 
   273       T top() const {
   274 	return top_right.y;
   275       }
   276 
   277       ///Gives back the left side of the box (if the bounding box is empty, then the return value is not defined) 
   278       T left() const {
   279 	return bottom_left.x;
   280       }
   281 
   282       ///Gives back the right side of the box (if the bounding box is empty, then the return value is not defined) 
   283       T right() const {
   284 	return top_right.x;
   285       }
   286 
   287       ///Gives back the height of the box (if the bounding box is empty, then the return value is not defined) 
   288       T height() const {
   289 	return top_right.y-bottom_left.y;
   290       }
   291 
   292       ///Gives back the width of the box (if the bounding box is empty, then the return value is not defined) 
   293       T width() const {
   294 	return top_right.x-bottom_left.x;
   295       }
   296 
   297       ///Checks whether a point is inside a bounding box
   298       bool inside(const xy<T>& u){
   299 	if (_empty)
   300 	  return false;
   301 	else{
   302 	  return ((u.x-bottom_left.x)*(top_right.x-u.x) >= 0 &&
   303 		  (u.y-bottom_left.y)*(top_right.y-u.y) >= 0 );
   304 	}
   305       }
   306   
   307       ///Increments a bounding box with a point
   308       BoundingBox& operator +=(const xy<T>& u){
   309 	if (_empty){
   310 	  bottom_left=top_right=u;
   311 	  _empty = false;
   312 	}
   313 	else{
   314 	  if (bottom_left.x > u.x) bottom_left.x = u.x;
   315 	  if (bottom_left.y > u.y) bottom_left.y = u.y;
   316 	  if (top_right.x < u.x) top_right.x = u.x;
   317 	  if (top_right.y < u.y) top_right.y = u.y;
   318 	}
   319 	return *this;
   320       }
   321   
   322       ///Sums a bounding box and a point
   323       BoundingBox operator +(const xy<T>& u){
   324 	BoundingBox b = *this;
   325 	return b += u;
   326       }
   327 
   328       ///Increments a bounding box with an other bounding box
   329       BoundingBox& operator +=(const BoundingBox &u){
   330 	if ( !u.empty() ){
   331 	  *this += u.bottomLeft();
   332 	  *this += u.topRight();
   333 	}
   334 	return *this;
   335       }
   336   
   337       ///Sums two bounding boxes
   338       BoundingBox operator +(const BoundingBox& u){
   339 	BoundingBox b = *this;
   340 	return b += u;
   341       }
   342 
   343     };//class Boundingbox
   344 
   345 
   346   ///Map of x-coordinates of an xy<>-map
   347 
   348   ///\ingroup maps
   349   ///
   350   template<class M>
   351   class XMap 
   352   {
   353     M &_map;
   354   public:
   355     typedef typename M::Value::Value Value;
   356     typedef typename M::Key Key;
   357     ///\e
   358     XMap(M &map) : _map(map) {}
   359     Value operator[](Key k) const {return _map[k].x;}
   360     void set(Key k,Value v) {_map.set(k,typename M::Value(v,_map[k].y));}
   361   };
   362     
   363   ///Returns an \ref XMap class
   364 
   365   ///This function just returns an \ref XMap class.
   366   ///
   367   ///\ingroup maps
   368   ///\relates XMap
   369   template<class M> 
   370   inline XMap<M> xMap(M &m) 
   371   {
   372     return XMap<M>(m);
   373   }
   374 
   375   ///Constant (read only) version of \ref XMap
   376 
   377   ///\ingroup maps
   378   ///
   379   template<class M>
   380   class ConstXMap 
   381   {
   382     const M &_map;
   383   public:
   384     typedef typename M::Value::Value Value;
   385     typedef typename M::Key Key;
   386     ///\e
   387     ConstXMap(const M &map) : _map(map) {}
   388     Value operator[](Key k) const {return _map[k].x;}
   389   };
   390     
   391   ///Returns a \ref ConstXMap class
   392 
   393   ///This function just returns an \ref ConstXMap class.
   394   ///
   395   ///\ingroup maps
   396   ///\relates ConstXMap
   397   template<class M> 
   398   inline ConstXMap<M> xMap(const M &m) 
   399   {
   400     return ConstXMap<M>(m);
   401   }
   402 
   403   ///Map of y-coordinates of an xy<>-map
   404     
   405   ///\ingroup maps
   406   ///
   407   template<class M>
   408   class YMap 
   409   {
   410     M &_map;
   411   public:
   412     typedef typename M::Value::Value Value;
   413     typedef typename M::Key Key;
   414     ///\e
   415     YMap(M &map) : _map(map) {}
   416     Value operator[](Key k) const {return _map[k].y;}
   417     void set(Key k,Value v) {_map.set(k,typename M::Value(_map[k].x,v));}
   418   };
   419 
   420   ///Returns an \ref YMap class
   421 
   422   ///This function just returns an \ref YMap class.
   423   ///
   424   ///\ingroup maps
   425   ///\relates YMap
   426   template<class M> 
   427   inline YMap<M> yMap(M &m) 
   428   {
   429     return YMap<M>(m);
   430   }
   431 
   432   ///Constant (read only) version of \ref YMap
   433 
   434   ///\ingroup maps
   435   ///
   436   template<class M>
   437   class ConstYMap 
   438   {
   439     const M &_map;
   440   public:
   441     typedef typename M::Value::Value Value;
   442     typedef typename M::Key Key;
   443     ///\e
   444     ConstYMap(const M &map) : _map(map) {}
   445     Value operator[](Key k) const {return _map[k].y;}
   446   };
   447     
   448   ///Returns a \ref ConstYMap class
   449 
   450   ///This function just returns an \ref ConstYMap class.
   451   ///
   452   ///\ingroup maps
   453   ///\relates ConstYMap
   454   template<class M> 
   455   inline ConstYMap<M> yMap(const M &m) 
   456   {
   457     return ConstYMap<M>(m);
   458   }
   459 
   460 
   461   ///Map of the \ref xy::normSquare() "normSquare()" of an \ref xy "xy"-map
   462 
   463   ///Map of the \ref xy::normSquare() "normSquare()" of an \ref xy "xy"-map
   464   ///\ingroup maps
   465   ///
   466   template<class M>
   467   class NormSquareMap 
   468   {
   469     const M &_map;
   470   public:
   471     typedef typename M::Value::Value Value;
   472     typedef typename M::Key Key;
   473     ///\e
   474     NormSquareMap(const M &map) : _map(map) {}
   475     Value operator[](Key k) const {return _map[k].normSquare();}
   476   };
   477     
   478   ///Returns a \ref NormSquareMap class
   479 
   480   ///This function just returns an \ref NormSquareMap class.
   481   ///
   482   ///\ingroup maps
   483   ///\relates NormSquareMap
   484   template<class M> 
   485   inline NormSquareMap<M> normSquareMap(const M &m) 
   486   {
   487     return NormSquareMap<M>(m);
   488   }
   489 
   490   /// @}
   491 
   492 
   493 } //namespace lemon
   494 
   495 #endif //LEMON_XY_H