Compilation of the ITS upgrade libraries (Annalisa, Stefan)

[u/mrichter/AliRoot.git] / FMD / flow / AliFMDFlowEventPlane.h

diff --git a/FMD/flow/AliFMDFlowEventPlane.h b/FMD/flow/AliFMDFlowEventPlane.h
index 8258eaba5680e1aa2a69bdaba51f7d2307bf101e..5e5ff12be85a17d28a1a422bea904c548a958c25 100644 (file)
--- a/FMD/flow/AliFMDFlowEventPlane.h
+++ b/FMD/flow/AliFMDFlowEventPlane.h
@@ -1,9 +1,40 @@
 // -*- C++ -*- 
+/* Copyright (C) 2007 Christian Holm Christensen <cholm@nbi.dk>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+ * USA
+ */
 /** @file 
     @brief Declaration of an EventPlane class */
-#ifndef FLOW_EVENTPLANE_H
-#define FLOW_EVENTPLANE_H
+//____________________________________________________________________
+//
+// Class to determine the event plane 
+// 
+// The event plane is calculated as 
+// 
+//    Psi_n = 1/n * atan((sum_i(w_i sin(n phi_i)))
+//                        sum_i(w_i cos(n phi_i))))
+//
+// where i runs over all observations of phi in an event, and 
+// w_i is the weight of the ith observation of phi
+#ifndef ALIFMDFLOWEVENTPLANE_H
+#define ALIFMDFLOWEVENTPLANE_H
 #include <TObject.h>
+#include <TH2D.h>
+#include <TH1D.h>
+class TBrowser;
 
 //______________________________________________________
 /** @class AliFMDFlowEventPlane flow/AliFMDFlowEventPlane.h <flow/AliFMDFlowEventPlane.h>
@@ -25,20 +56,19 @@ class AliFMDFlowEventPlane : public TObject
 public:
   /** Constructor 
       @param m Harmonic number */
-  AliFMDFlowEventPlane(UShort_t m) 
-    : fSumSinMPhi(0), 
-      fSumCosMPhi(0),
-      fOrder(m),
-      fCache(0)
-  { Clear(); }
+  AliFMDFlowEventPlane(UShort_t m=0);
+  /** Copy constructor. 
+      @param o Object to copy from */ 
+  AliFMDFlowEventPlane(const AliFMDFlowEventPlane& o);
+  /** Assignement operator. 
+      @param o Object to copy from 
+      @return Reference to this */
+  AliFMDFlowEventPlane& operator=(const AliFMDFlowEventPlane& o);
   /** Destructor */
   ~AliFMDFlowEventPlane() {} 
-  /** Clear it */
-  void Clear(Option_t* option="");
-  /** Add a data point 
-      @param phi The angle @f$\varphi\in[0,2\pi]@f$
-      @param weight The weight */
-  void Add(Double_t phi, Double_t weight=1);
+
+  /** @{ 
+      @name Information */
   /** Get the event plane 
       @return @f$ \Psi_k@f$ */
   Double_t Psi() const;
@@ -53,6 +83,35 @@ public:
   /** Get the harmnic order 
       @return @f$ k@f$  */
   UShort_t Order() const { return fOrder; }
+  /** @} */
+
+  /** @{ 
+      @name Processing */
+  /** Clear it */
+  void Clear(Option_t* option="");
+  /** Add a data point 
+      @param phi The angle @f$\varphi\in[0,2\pi]@f$
+      @param weight The weight */
+  void Add(Double_t phi, Double_t weight=1);
+  /** Called at end of event to fill histograms */
+  void End();
+  /** @} */
+  
+  /** @{ 
+      @name Utilities */
+  /** this is a folder */ 
+  Bool_t IsFolder() const { return kTRUE; }
+  /** Browse this object */
+  void Browse(TBrowser* b);
+  /** @} */
+
+  /** @{ 
+      @name histograms */ 
+  /** @return Sum histogram */
+  const TH2& SumHistogram() const { return fSum; }
+  /** @return Psi histogram */
+  const TH1& PsiHistogram() const { return fPsi; }
+  /** @} */
 protected:
   /** Utility function to calculate @f$ \Psi@f$ from the sum of
       sines and cosines. 
@@ -61,13 +120,19 @@ protected:
       @return @f$ \Psi@f$ */
   Double_t DoPsi(Double_t sumsin, Double_t sumcos) const;
   /** @f$ \sum_i w_i \sin(k \varphi_i)@f$ */
-  Double_t fSumSinMPhi;
+  Double_t fSumSinMPhi; // Sum of contributions 
   /** @f$ \sum_i w_i \cos(k \varphi_i)@f$ */
-  Double_t fSumCosMPhi;
+  Double_t fSumCosMPhi; // Sum of contributions 
   /** Order */
-  UShort_t fOrder;
+  UShort_t fOrder; // Order 
   /** Cache of Psi */
-  mutable Double_t fCache;
+  mutable Double_t fCache; // Cache of calculated value 
+  /** Histogram of summed sin(m*phi) vs cos(m*phi) */
+  TH2D fSum;
+  /** Histogram of event plane angles */ 
+  TH1D fPsi;
+  /** Counter */ 
+  Double_t fScale;
   /** Define for ROOT I/O */
   ClassDef(AliFMDFlowEventPlane,1); 
 };