source: trunk/Mars/mbase/MQuaternion.cc@ 18716

Last change on this file since 18716 was 9234, checked in by tbretz, 16 years ago
*** empty log message ***
File size: 3.0 KB
Line 
1/* ======================================================================== *\
2!
3! *
4! * This file is part of MARS, the MAGIC Analysis and Reconstruction
5! * Software. It is distributed to you in the hope that it can be a useful
6! * and timesaving tool in analysing Data of imaging Cerenkov telescopes.
7! * It is distributed WITHOUT ANY WARRANTY.
8! *
9! * Permission to use, copy, modify and distribute this software and its
10! * documentation for any purpose is hereby granted without fee,
11! * provided that the above copyright notice appear in all copies and
12! * that both that copyright notice and this permission notice appear
13! * in supporting documentation. It is provided "as is" without express
14! * or implied warranty.
15! *
16!
17!
18! Author(s): Thomas Bretz 11/2008 <mailto:tbretz@astro.uni-wuerzburg.de>
19!
20! Copyright: MAGIC Software Development, 2000-2009
21!
22!
23\* ======================================================================== */
24
25//////////////////////////////////////////////////////////////////////////////
26//
27// MQuaternion
28//
29// The MQuaternion is derived from TQuaternion. A quaternion is a four vector
30// which can store space and time (like a lorentz vector).
31//
32// There are a few advantages of the TQuaternion class over the
33// TLorentzVector, namely the implementation of a direct algebra with
34// just the space part of the vector keeping the time as it is.
35// (This is useful, e.g, for rotations and shift just in space).
36//
37// - You can construct the MQuaternion from a TQuaternion or a TVector3 and
38// time.
39// - Multiplying the MQuaternion with a TRotation with rotate just the
40// space-part.
41// - You can access the data members with X(), Y(), Z() and T()
42// - To get the length or squared-length of the space-vector use R() and R2()
43// - Access the 2D vector (x/y) with XYvector()
44// - Thera are a few new function to propagate a MQuaternion along a trajectory
45// in space and time (also expressed as an MQuaternion with a direction
46// vector and a speed) Here we assume v>0.
47//
48// + PropagateDz(MQuaternion &w, Double_t dz)
49//
50// If dz is positive the position is propagated along the given trajectory
51// in space (such that the z-component will increase by dz) and
52// forward in time. If dz<0 the result is vice versa.
53//
54// + PropagateZ0(MQuaternion &w)
55//
56// This is an abbreviation for Propagate(w, -Z()). It propagates the
57// position such that its z-component will vanish. If this is along
58// the given trajectory time will increase if it is backward time
59// will decrease.
60//
61// + PropagateZ(MQuaternion &w, Double_t z)
62//
63// This is an abbreviation for Propagate(w, z-Z()). It propagates the
64// position such that its z-component will become z. If this is along
65// the given trajectory time will increase if it is backward time
66// will decrease.
67//
68//////////////////////////////////////////////////////////////////////////////
69#include "MQuaternion.h"
70
71ClassImp(MQuaternion);
72
73using namespace std;
74
Note: See TracBrowser for help on using the repository browser.