First version of the AOD classes (Markus, Federico)

[u/mrichter/AliRoot.git] / STEER / AliRedCov.cxx

diff --git a/STEER/AliRedCov.cxx b/STEER/AliRedCov.cxx
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+/**************************************************************************
+ * Copyright(c) 1998-2007, ALICE Experiment at CERN, All rights reserved. *
+ *                                                                        *
+ * Author: The ALICE Off-line Project.                                    *
+ * Contributors are mentioned in the code where appropriate.              *
+ *                                                                        *
+ * Permission to use, copy, modify and distribute this software and its   *
+ * documentation strictly for non-commercial purposes is hereby granted   *
+ * without fee, provided that the above copyright notice appears in all   *
+ * copies and that both the copyright notice and this permission notice   *
+ * appear in the supporting documentation. The authors make no claims     *
+ * about the suitability of this software for any purpose. It is          *
+ * provided "as is" without express or implied warranty.                  *
+ **************************************************************************/
+
+/* $Id$ */
+
+#include <TMath.h>
+
+#include "AliRedCov.h"
+
+templateClassImp(AliRedCov)
+
+//______________________________________________________________________________
+template <Int_t N> template <class T> void AliRedCov<N>::GetCovMatrix(T *cmat) const
+{
+  //
+  // Returns the external cov matrix
+  //
+
+  for(Int_t i=0; i<N; ++i) {
+    // Off diagonal elements
+    for(Int_t j=0; j<i; ++j) {
+      printf("cmat[%2d] = fODia[%2d]*fDiag[%2d]*fDiag[%2d];\n",
+            i*(i+1)/2+j,(i-1)*i/2+j,j,i);
+      cmat[i*(i+1)/2+j] = fODia[(i-1)*i/2+j]*fDiag[j]*fDiag[i];}
+
+    // Diagonal elements
+    printf("cmat[%2d] = fDiag[%2d]*fDiag[%2d];\n",
+          i*(i+1)/2+i,i,i);
+    cmat[i*(i+1)/2+i] = fDiag[i]*fDiag[i];
+  }
+}
+
+
+//______________________________________________________________________________
+template <Int_t N> template <class T> void AliRedCov<N>::SetCovMatrix(T *cmat)
+{
+  //
+  // Sets the external cov matrix
+  //
+
+  if(cmat) {
+    // Diagonal elements first
+    for(Int_t i=0; i<N; ++i) {
+      printf("fDiag[%2d] = TMath::Sqrt(cmat[%2d]);\n",
+            i,i*(i+1)/2+i);
+      fDiag[i] = TMath::Sqrt(cmat[i*(i+1)/2+i]);}
+
+  // ... then the ones off diagonal
+  for(Int_t i=0; i<N; ++i) 
+    // Off diagonal elements
+    for(Int_t j=0; j<i; ++j) {
+      printf("fODia[%2d] = cmat[%2d]/(fDiag[%2d]*fDiag[%2d]);\n",
+            (i-1)*i/2+j,i*(i+1)/2+j,j,i);
+      fODia[(i-1)*i/2+j] = cmat[i*(i+1)/2+j]/(fDiag[j]*fDiag[i]);
+    }
+  } else {
+    for(Int_t i=0; i< N; ++i) fDiag[i]=-999.;
+    for(Int_t i=0; i< N*(N-1)/2; ++i) fODia[i]=0.;
+  }
+}