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DisplacementVector2D.h
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1// @(#)root/mathcore:$Id$
2// Authors: W. Brown, M. Fischler, L. Moneta 2005
3
4 /**********************************************************************
5 * *
6 * Copyright (c) 2005 , LCG ROOT MathLib Team and *
7 * FNAL LCG ROOT MathLib Team *
8 * *
9 * *
10 **********************************************************************/
11
12// Header source file for class DisplacementVector2D
13//
14// Created by: Lorenzo Moneta at Mon Apr 16 2007
15//
16
17#ifndef ROOT_Math_GenVector_DisplacementVector2D
18#define ROOT_Math_GenVector_DisplacementVector2D 1
19
21
23
25
27
29
30//#include "Math/GenVector/Expression2D.h"
31
32
33
34
35namespace ROOT {
36
37 namespace Math {
38
39
40
41//__________________________________________________________________________________________
42 /**
43 Class describing a generic displacement vector in 2 dimensions.
44 This class is templated on the type of Coordinate system.
45 One example is the XYVector which is a vector based on
46 double precision x,y data members by using the
47 ROOT::Math::Cartesian2D<double> Coordinate system.
48 The class is having also an extra template parameter, the coordinate system tag,
49 to be able to identify (tag) vector described in different reference coordinate system,
50 like global or local coordinate systems.
51
52 @ingroup GenVector
53 */
54
55 template <class CoordSystem, class Tag = DefaultCoordinateSystemTag >
57
58 public:
59
60 typedef typename CoordSystem::Scalar Scalar;
61 typedef CoordSystem CoordinateType;
63
64 // ------ ctors ------
65
66 /**
67 Default constructor. Construct an empty object with zero values
68 */
70
71
72 /**
73 Construct from three values of type <em>Scalar</em>.
74 In the case of a XYVector the values are x,y
75 In the case of a polar vector they are r, phi
76 */
78 fCoordinates ( a , b ) { }
79
80 /**
81 Construct from a displacement vector expressed in different
82 coordinates, or using a different Scalar type, but with same coordinate system tag
83 */
84 template <class OtherCoords>
86 fCoordinates ( v.Coordinates() ) { }
87
88
89 /**
90 Construct from a position vector expressed in different coordinates
91 but with the same coordinate system tag
92 */
93 template <class OtherCoords>
95 fCoordinates ( p.Coordinates() ) { }
96
97
98 /**
99 Construct from a foreign 2D vector type, for example, Hep2Vector
100 Precondition: v must implement methods x() and y()
101 */
102 template <class ForeignVector>
103 explicit DisplacementVector2D( const ForeignVector & v) :
104 fCoordinates ( Cartesian2D<Scalar>( v.x(), v.y() ) ) { }
105
106
107
108 // compiler-generated copy ctor and dtor are fine.
109
110 // ------ assignment ------
111
112 /**
113 Assignment operator from a displacement vector of arbitrary type
114 */
115 template <class OtherCoords>
118 fCoordinates = v.Coordinates();
119 return *this;
120 }
121
122 /**
123 Assignment operator from a position vector
124 (not necessarily efficient unless one or the other is Cartesian)
125 */
126 template <class OtherCoords>
128 ( const PositionVector2D<OtherCoords,Tag> & rhs) {
129 SetXY(rhs.x(), rhs.y() );
130 return *this;
131 }
132
133
134 /**
135 Assignment from a foreign 2D vector type, for example, Hep2Vector
136 Precondition: v must implement methods x() and y()
137 */
138 template <class ForeignVector>
139 DisplacementVector2D & operator= ( const ForeignVector & v) {
140 SetXY( v.x(), v.y() );
141 return *this;
142 }
143
144
145 // ------ Set, Get, and access coordinate data ------
146
147 /**
148 Retrieve a copy of the coordinates object
149 */
150 CoordSystem Coordinates() const {
151 return fCoordinates;
152 }
153
154 /**
155 Set internal data based on 2 Scalar numbers.
156 These are for example (x,y) for a cartesian vector or (r,phi) for a polar vector
157 */
159 fCoordinates.SetCoordinates(a, b);
160 return *this;
161 }
162
163
164 /**
165 get internal data into 2 Scalar numbers.
166 These are for example (x,y) for a cartesian vector or (r,phi) for a polar vector
167 */
169 { fCoordinates.GetCoordinates(a, b); }
170
171
172 /**
173 set the values of the vector from the cartesian components (x,y)
174 (if the vector is held in polar coordinates,
175 then (x, y) are converted to that form)
176 */
178 fCoordinates.SetXY(a,b);
179 return *this;
180 }
181
182 // ------------------- Equality -----------------
183
184 /**
185 Exact equality
186 */
187 bool operator==(const DisplacementVector2D & rhs) const {
188 return fCoordinates==rhs.fCoordinates;
189 }
190 bool operator!= (const DisplacementVector2D & rhs) const {
191 return !(operator==(rhs));
192 }
193
194 // ------ Individual element access, in various coordinate systems ------
195
196 /**
197 Cartesian X, converting if necessary from internal coordinate system.
198 */
199 Scalar X() const { return fCoordinates.X(); }
200
201 /**
202 Cartesian Y, converting if necessary from internal coordinate system.
203 */
204 Scalar Y() const { return fCoordinates.Y(); }
205
206
207 /**
208 Polar R, converting if necessary from internal coordinate system.
209 */
210 Scalar R() const { return fCoordinates.R(); }
211
212
213 /**
214 Polar phi, converting if necessary from internal coordinate system.
215 */
216 Scalar Phi() const { return fCoordinates.Phi(); }
217
218
219 // ----- Other fundamental properties -----
220
221 /**
222 Magnitute squared ( r^2 in spherical coordinate)
223 */
224 Scalar Mag2() const { return fCoordinates.Mag2();}
225
226
227 /**
228 return unit vector parallel to this
229 */
231 Scalar tot = R();
232 return tot == 0 ? *this : DisplacementVector2D(*this) / tot;
233 }
234
235 // ------ Setting individual elements present in coordinate system ------
236
237 /**
238 Change X - Cartesian2D coordinates only
239 */
241 fCoordinates.SetX(a);
242 return *this;
243 }
244
245 /**
246 Change Y - Cartesian2D coordinates only
247 */
249 fCoordinates.SetY(a);
250 return *this;
251 }
252
253
254 /**
255 Change R - Polar2D coordinates only
256 */
258 fCoordinates.SetR(a);
259 return *this;
260 }
261
262
263 /**
264 Change Phi - Polar2D coordinates
265 */
267 fCoordinates.SetPhi(ang);
268 return *this;
269 }
270
271
272
273 // ------ Operations combining two vectors ------
274 // -- need to have the specialized version in order to avoid
275
276 /**
277 Return the scalar (dot) product of two displacement vectors.
278 It is possible to perform the product for any type of vector coordinates,
279 but they must have the same coordinate system tag
280 */
281 template< class OtherCoords >
283 return X()*v.X() + Y()*v.Y();
284 }
285 /**
286 Return the scalar (dot) product of two vectors.
287 It is possible to perform the product for any classes
288 implementing x() and y() member functions
289 */
290 template< class OtherVector >
291 Scalar Dot( const OtherVector & v) const {
292 return X()*v.x() + Y()*v.y();
293 }
294
295
296
297 /**
298 Self Addition with a displacement vector.
299 */
300 template <class OtherCoords>
303 SetXY( X() + v.X(), Y() + v.Y() );
304 return *this;
305 }
306
307 /**
308 Self Difference with a displacement vector.
309 */
310 template <class OtherCoords>
313 SetXY( x() - v.x(), y() - v.y() );
314 return *this;
315 }
316
317
318 /**
319 multiply this vector by a scalar quantity
320 */
322 fCoordinates.Scale(a);
323 return *this;
324 }
325
326 /**
327 divide this vector by a scalar quantity
328 */
330 fCoordinates.Scale(1/a);
331 return *this;
332 }
333
334 // -- The following methods (v*a and v/a) could instead be free functions.
335 // -- They were moved into the class to solve a problem on AIX.
336
337 /**
338 Multiply a vector by a real number
339 */
341 DisplacementVector2D tmp(*this);
342 tmp *= a;
343 return tmp;
344 }
345
346 /**
347 Negative of the vector
348 */
350 return operator*( Scalar(-1) );
351 }
352
353 /**
354 Positive of the vector, return itself
355 */
356 DisplacementVector2D operator + ( ) const {return *this;}
357
358 /**
359 Division of a vector with a real number
360 */
362 DisplacementVector2D tmp(*this);
363 tmp /= a;
364 return tmp;
365 }
366
367 /**
368 Rotate by an angle
369 */
370 void Rotate( Scalar angle) {
371 return fCoordinates.Rotate(angle);
372 }
373
374
375 // Methods providing Limited backward name compatibility with CLHEP
376
377 Scalar x() const { return fCoordinates.X(); }
378 Scalar y() const { return fCoordinates.Y(); }
379 Scalar r() const { return fCoordinates.R(); }
380 Scalar phi() const { return fCoordinates.Phi(); }
381 Scalar mag2() const { return fCoordinates.Mag2(); }
382 DisplacementVector2D unit() const {return Unit();}
383
384
385 private:
386
387 CoordSystem fCoordinates; // internal coordinate system
388
389
390 // the following methods should not compile
391
392 // this should not compile (if from a vector or points with different tag
393 template <class OtherCoords, class OtherTag>
395
396 template <class OtherCoords, class OtherTag>
398
399 template <class OtherCoords, class OtherTag>
401
402
403 template <class OtherCoords, class OtherTag>
405
406 template <class OtherCoords, class OtherTag>
408
409 template <class OtherCoords, class OtherTag>
411
412 template<class OtherCoords, class OtherTag >
414
415 template<class OtherCoords, class OtherTag >
417
418
419 };
420
421// ---------- DisplacementVector2D class template ends here ------------
422// ---------------------------------------------------------------------
423
424
425 /**
426 Addition of DisplacementVector2D vectors.
427 The (coordinate system) type of the returned vector is defined to
428 be identical to that of the first vector, which is passed by value
429 */
430 template <class CoordSystem1, class CoordSystem2, class U>
431 inline
435 return v1 += v2;
436 }
437
438 /**
439 Difference between two DisplacementVector2D vectors.
440 The (coordinate system) type of the returned vector is defined to
441 be identical to that of the first vector.
442 */
443 template <class CoordSystem1, class CoordSystem2, class U>
444 inline
445 DisplacementVector2D<CoordSystem1,U>
448 return v1 -= v2;
449 }
450
451
452
453
454
455 /**
456 Multiplication of a displacement vector by real number a*v
457 */
458 template <class CoordSystem, class U>
459 inline
460 DisplacementVector2D<CoordSystem,U>
463 return v *= a;
464 // Note - passing v by value and using operator *= may save one
465 // copy relative to passing v by const ref and creating a temporary.
466 }
467
468
469 // v1*v2 notation for Cross product of two vectors is omitted,
470 // since it is always confusing as to whether dot product is meant.
471
472
473
474 // ------------- I/O to/from streams -------------
475
476 template< class char_t, class traits_t, class T, class U >
477 inline
478 std::basic_ostream<char_t,traits_t> &
479 operator << ( std::basic_ostream<char_t,traits_t> & os
480 , DisplacementVector2D<T,U> const & v
481 )
482 {
483 if( !os ) return os;
484
485 typename T::Scalar a, b;
486 v.GetCoordinates(a, b);
487
490 typedef GenVector_detail::BitReproducible BR;
491 BR::Output(os, a);
492 BR::Output(os, b);
493 }
494 else {
495 os << detail::get_manip( os, detail::open ) << a
496 << detail::get_manip( os, detail::sep ) << b
498 }
499
500 return os;
501
502 } // op<< <>()
503
504
505 template< class char_t, class traits_t, class T, class U >
506 inline
507 std::basic_istream<char_t,traits_t> &
508 operator >> ( std::basic_istream<char_t,traits_t> & is
510 )
511 {
512 if( !is ) return is;
513
514 typename T::Scalar a, b;
515
519 BR::Input(is, a);
520 BR::Input(is, b);
521 }
522 else {
524 detail::require_delim( is, detail::sep ); is >> b;
526 }
527
528 if( is )
529 v.SetCoordinates(a, b);
530 return is;
531
532 } // op>> <>()
533
534
535
536 } // namespace Math
537
538} // namespace ROOT
539
540
541#endif /* ROOT_Math_GenVector_DisplacementVector2D */
542
SVector< double, 2 > v
Definition: Dict.h:5
#define b(i)
Definition: RSha256.hxx:100
Class describing a 2D cartesian coordinate system (x, y coordinates)
Definition: Cartesian2D.h:37
Class describing a generic displacement vector in 2 dimensions.
DisplacementVector2D()
Default constructor.
Scalar Mag2() const
Magnitute squared ( r^2 in spherical coordinate)
DisplacementVector2D(Scalar a, Scalar b)
Construct from three values of type Scalar.
DisplacementVector2D(const ForeignVector &v)
Construct from a foreign 2D vector type, for example, Hep2Vector Precondition: v must implement metho...
Scalar X() const
Cartesian X, converting if necessary from internal coordinate system.
DisplacementVector2D Cross(const DisplacementVector2D< OtherCoords, OtherTag > &) const
Scalar R() const
Polar R, converting if necessary from internal coordinate system.
DisplacementVector2D & operator=(const DisplacementVector2D< OtherCoords, OtherTag > &)
DisplacementVector2D< CoordSystem, Tag > & SetY(Scalar a)
Change Y - Cartesian2D coordinates only.
DisplacementVector2D & operator=(const DisplacementVector2D< OtherCoords, Tag > &v)
Assignment operator from a displacement vector of arbitrary type.
DisplacementVector2D operator+() const
Positive of the vector, return itself.
DisplacementVector2D operator-() const
Negative of the vector.
Scalar Dot(const OtherVector &v) const
Return the scalar (dot) product of two vectors.
CoordSystem Coordinates() const
Retrieve a copy of the coordinates object.
bool operator==(const DisplacementVector2D &rhs) const
Exact equality.
DisplacementVector2D< CoordSystem, Tag > & SetCoordinates(Scalar a, Scalar b)
Set internal data based on 2 Scalar numbers.
Scalar Phi() const
Polar phi, converting if necessary from internal coordinate system.
DisplacementVector2D(const DisplacementVector2D< OtherCoords, OtherTag > &)
Scalar Y() const
Cartesian Y, converting if necessary from internal coordinate system.
Scalar Dot(const DisplacementVector2D< OtherCoords, OtherTag > &) const
DisplacementVector2D & operator*=(Scalar a)
multiply this vector by a scalar quantity
DisplacementVector2D & operator-=(const DisplacementVector2D< OtherCoords, OtherTag > &)
DisplacementVector2D< CoordSystem, Tag > & SetPhi(Scalar ang)
Change Phi - Polar2D coordinates.
DisplacementVector2D & operator+=(const DisplacementVector2D< OtherCoords, OtherTag > &)
DisplacementVector2D & operator=(const PositionVector2D< OtherCoords, OtherTag > &)
DisplacementVector2D & operator/=(Scalar a)
divide this vector by a scalar quantity
bool operator!=(const DisplacementVector2D &rhs) const
DisplacementVector2D unit() const
void Rotate(Scalar angle)
Rotate by an angle.
DisplacementVector2D< CoordSystem, Tag > & SetX(Scalar a)
Change X - Cartesian2D coordinates only.
DisplacementVector2D< CoordSystem, Tag > & SetR(Scalar a)
Change R - Polar2D coordinates only.
DisplacementVector2D(const DisplacementVector2D< OtherCoords, Tag > &v)
Construct from a displacement vector expressed in different coordinates, or using a different Scalar ...
DisplacementVector2D(const PositionVector2D< OtherCoords, OtherTag > &)
Scalar Dot(const DisplacementVector2D< OtherCoords, Tag > &v) const
Return the scalar (dot) product of two displacement vectors.
void GetCoordinates(Scalar &a, Scalar &b) const
get internal data into 2 Scalar numbers.
DisplacementVector2D operator*(Scalar a) const
Multiply a vector by a real number.
DisplacementVector2D(const PositionVector2D< OtherCoords, Tag > &p)
Construct from a position vector expressed in different coordinates but with the same coordinate syst...
DisplacementVector2D operator/(Scalar a) const
Division of a vector with a real number.
DisplacementVector2D< CoordSystem, Tag > & SetXY(Scalar a, Scalar b)
set the values of the vector from the cartesian components (x,y) (if the vector is held in polar coor...
DisplacementVector2D Unit() const
return unit vector parallel to this
Class describing a generic position vector (point) in 2 dimensions.
Namespace for new Math classes and functions.
char_t get_manip(std::basic_ios< char_t, traits_t > &ios, manip_t m)
Definition: GenVectorIO.h:54
std::basic_istream< char_t, traits_t > & require_delim(std::basic_istream< char_t, traits_t > &is, manip_t m)
Definition: GenVectorIO.h:113
void set_manip(std::basic_ios< char_t, traits_t > &ios, manip_t m, char_t ch)
Definition: GenVectorIO.h:74
std::ostream & operator<<(std::ostream &os, const AxisAngle &a)
Stream Output and Input.
Definition: AxisAngle.cxx:91
std::basic_istream< char_t, traits_t > & operator>>(std::basic_istream< char_t, traits_t > &is, DisplacementVector2D< T, U > &v)
DisplacementVector2D< CoordSystem1, U > operator+(DisplacementVector2D< CoordSystem1, U > v1, const DisplacementVector2D< CoordSystem2, U > &v2)
Addition of DisplacementVector2D vectors.
DisplacementVector2D< CoordSystem1, U > operator-(DisplacementVector2D< CoordSystem1, U > v1, DisplacementVector2D< CoordSystem2, U > const &v2)
Difference between two DisplacementVector2D vectors.
AxisAngle operator*(RotationX const &r1, AxisAngle const &r2)
Multiplication of an axial rotation by an AxisAngle.
Rotation3D::Scalar Scalar
Namespace for new ROOT classes and functions.
Definition: StringConv.hxx:21
auto * a
Definition: textangle.C:12