A more complex example

Fit a background with a P3

      Macro PAWEX15A ID=30001 IP1=40 IP2=111 IZ1=33 IZ2=150 LOOP=20
*
      Set 2BUF 1
      Hi/file 1 pawtut.hbook ; Hrin [ID]
      Set FWID 6 ; Set DMOD 1
1     NBIN = $HINFO([ID],'XBINS')                                                              
      Vector/Create  FUNC([NBIN])
      Vector/Create  Y([NBIN])
      Vector/Create  S([NBIN])
      Vector/Create  X([NBIN],[LOOP])
      Histogram/Copy [ID] 1
      Histogram/Copy [ID] 2
*
2     Do i=1,[LOOP]                                                                            
         Histogram/Plot 1
3        Histogram/Fit  1([IZ1]:[IZ2]) P3 0q                                                   
3        Get/Func 1 FUNC ; Put/Cont 2 FUNC                                                     
3        Sub 1 2 3                                                                             
4        Histogram/Fit  3([IP1]:[IP2]) G 0q                                                    
         Histogram/Plot 3([IP1]:[IP2]) FUNCS
4        Get/Func 3 FUNC ; Put/Cont 2 FUNC                                                     
4        Sub 1 2 1                                                                             
         Get/Func 3 X(1:[NBIN],[i])
         Call igterm
      Enddo
*
      Get/Func 1 FUNC ; Put/Cont 2 FUNC
      Sub [id] 2 3
      Zone 1 2
      Histogram/Plot [ID]
      Histogram/Plot 1 FUNCS
5     Do i=1,[LOOP]                                                                            
         Vector/Copy X(1:[NBIN],[i]) Y
         SIGMA S = S + Y
         SIGMA Y = Y+FUNC
         Put/Cont 2 Y
         Histogram/Plot 2([IP1]:[IP2]) SL
      Enddo
      Histogram/Plot 3([IP1]:[IP2]) HIST
      Put/Cont 2 S
      Histogram/plot 2([IP1]:[IP2]) Sl
*
      Close 1
      V/Del FUNC,X,Y,S ; H/Del 1,2,3
  1. This system function allows to retrieve informations on an histogram. Note that in a COMIS program information about histograms can be retrieve with the routine HGIVE (see example below).
  2. This loop try to find a P3 background.
  3. After a P3 fit, a new histogram is booked with the fit value at each channel. This new histogram is consider as an approximation of the background and is removed from the original histogram.
  4. A gaussian fit allows to remove the pick.
  5. This loop produce the two final plots. 
How to retrieve histogram informations in a COMIS program

      subroutine hinfo(id)
      character*32 chtitl
      vector hid(6)
      call hgive(id,chtitl,ncx,xmin,xmax,ncy,ymin,ymax,nwt,loc)
      hid(1) = ncx
      hid(2) = xmin
      hid(3) = xmax
      hid(4) = ncy
      hid(5) = ymin
      hid(6) = ymax
      end

PAW TutorialLast update: 1999/04/01 14.58
Olivier.Couet@Cern.Ch