[Rivet-svn] r2567 - trunk/include/LWH

[blackhole at projects.hepforge.org]

Author: dgrell
Date: Wed Jul  7 11:06:40 2010
New Revision: 2567

Log:
Reverted [2456]. Need normalize() in ThePEG.

Modified:
   trunk/include/LWH/Histogram1D.h

Modified: trunk/include/LWH/Histogram1D.h
==============================================================================
--- trunk/include/LWH/Histogram1D.h	Wed Jul  7 09:58:08 2010	(r2566)
+++ trunk/include/LWH/Histogram1D.h	Wed Jul  7 11:06:40 2010	(r2567)
@@ -394,6 +394,40 @@
     }
 
     /**
+     * Scale the given histogram so that the integral over all bins
+     * (including overflow) gives \a intg. This function also corrects
+     * for the bin-widths, which means that it should only be run once
+     * for each histogram. Further rescaling must be done with the
+     * scale(double) function.
+     */
+    void normalize(double intg) {
+      double oldintg = sumAllBinHeights();
+      if ( oldintg == 0.0 ) return;
+      for ( int i = 0; i < ax->bins() + 2; ++i ) {
+        double fac = intg/oldintg;
+        if ( i >= 2 ) fac /= (ax->binUpperEdge(i - 2) - ax->binLowerEdge(i - 2));
+        sumw[i] *= fac;
+        sumxw[i] *= fac;
+        sumx2w[i] *= fac;
+        sumw2[i] *= fac*fac;
+      }
+    }
+
+    /**
+     * Return the integral over the histogram bins assuming it has been
+     * normalize()d.
+     */
+    // double integral() const {
+    //   double intg = sumw[0] + sumw[1];
+    //   for ( int i = 2; i < ax->bins() + 2; ++i )
+
+    // is this right? Leave out bin width factor?
+
+    //     intg += sumw[i]*(ax->binUpperEdge(i - 2) - ax->binLowerEdge(i - 2));
+    //   return intg;
+    // }
+
+    /**
      * Not implemented in LWH.
      * @return null pointer always.
      */