Changes related to the initialization of random numbers generators. Now one can use...
[u/mrichter/AliRoot.git] / STEER / AliRndm.cxx
1 /**************************************************************************
2  * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3  *                                                                        *
4  * Author: The ALICE Off-line Project.                                    *
5  * Contributors are mentioned in the code where appropriate.              *
6  *                                                                        *
7  * Permission to use, copy, modify and distribute this software and its   *
8  * documentation strictly for non-commercial purposes is hereby granted   *
9  * without fee, provided that the above copyright notice appears in all   *
10  * copies and that both the copyright notice and this permission notice   *
11  * appear in the supporting documentation. The authors make no claims     *
12  * about the suitability of this software for any purpose. It is          *
13  * provided "as is" without express or implied warranty.                  *
14  **************************************************************************/
15
16 /* $Id$ */
17
18 ///////////////////////////////////////////////////////////////////////////////
19 //                                                                           //
20 //   Wrapper for the root random number generator                            //
21 //                                                                           //
22 ///////////////////////////////////////////////////////////////////////////////
23
24 #include "TFile.h"
25 #include "TError.h"
26 #include "TRandom3.h"
27 #include "TSystem.h"
28
29 #include "AliRndm.h"
30
31 ClassImp(AliRndm)
32
33 //_______________________________________________________________________
34 AliRndm::AliRndm():
35   fRandom(gRandom)
36 {
37   // 
38   // Default ctor
39   //
40 }
41
42 //_______________________________________________________________________
43 AliRndm::AliRndm(const AliRndm& rn):
44   fRandom(gRandom)
45 {
46   //
47   // Copy constructor
48   //
49   rn.Copy(*this);
50 }
51
52 //_______________________________________________________________________
53 void AliRndm::Copy(AliRndm&) const
54 {
55   ::Fatal("Copy","Not implemented\n");
56 }
57
58
59 //_____________________________________________________________________________
60 void AliRndm::Rndm(Float_t* array, const Int_t size) const
61 {
62   //
63   // Return an array of n random numbers uniformly distributed 
64   // between 0 and 1 not included
65   //
66   for(Int_t i=0; i<size; i++) 
67 #ifdef CKNONE
68     array[i]=fRandom->Rndm();
69 #else
70     do array[i]=fRandom->Rndm(); while(0>=array[i] || array[i]>=1);
71 #endif
72 }
73
74 //_____________________________________________________________________________
75 void AliRndm::ReadRandom(const char *filename)
76 {
77   //
78   // Reads saved random generator status from filename
79   //
80   char *fntmp = gSystem->ExpandPathName(filename);
81   TFile *file = new TFile(fntmp,"r");
82   delete [] fntmp;
83   if(!file) {
84     printf("AliRndm:: Could not open file %s\n",filename);
85   } else {
86     if(!fRandom) fRandom = new TRandom();
87     fRandom->Read("Random");
88     file->Close();
89     delete file;
90   }
91 }
92
93 //_____________________________________________________________________________
94 void AliRndm::WriteRandom(const char *filename) const
95 {
96   //
97   // Writes random generator status to filename
98   //
99   char *fntmp = gSystem->ExpandPathName(filename);
100   TFile *file = new TFile(fntmp,"new");
101   delete [] fntmp;
102   if(!file) {
103     printf("AliRndm:: Could not open file %s\n",filename);
104   } else {
105     fRandom->Write();
106     file->Close();
107     delete file;
108   }
109 }