Use of Ntuple masks and loops

Use of Ntuple masks and loops
      hi/file 2 rwn_aptuple.hbook
      1dhisto 20 'Distribution by grade' 12 3 15
      max 20 700
      ntuple/plot 10.grade IDH=20
1     MASK/FILE STMASK n                                                                       
2     NT/LOOP 10 STEP=15>>STMASK(1)                                                            
      nt/loop 10 grade>4.and.step=13>>stmask(2)
      nt/loop 10 _
      (grade=13.and.step=10).or.(grade=14.and.step=7)>>stmask(3)
      NT/PLOT 10.GRADE _
      STMASK(1).OR.STMASK(2).OR.STMASK(3)>>STMASK(4) OPTION=S IDH=20
3     MASK/LIST STMASK                                                                         
4     MASK/CLOSE STMASK                                                                        
      set CHHE 0.35
5     EXEC LEGEND 245 9.3 10.3 610 640 'All Staff'                                             
5     EXEC LEGEND 244 9.3 10.3 560 590 'Staff at end of grade'

NT/MASK perform operations with masks. A mask is a direct-access file with the name MNAME.MASK (here STMASK.MASK ). It must contain as many 32 bit words as there are events in the associated Ntuple. Masks are interesting when only a few events of a Ntuple are selected with a time consuming selection algorithm.
The symbol ``>>'' in NT/LOOP and NT/PLOT allows to fill the mask according to the selection function.
This command allows to print the definition of the mask.
The command MASK/CLOSE close the mask.
A general macro to draw a legend (see next page).
Try NT/PLOT 10.GRADE STMASK(4) : It produce the same result as the last NT/PLOT of the macro.

Compare the execution time (with TIMING ) of the two following commands:

  NTUPLE/PLOT 10.GRADE (GRADE=13.AND.STEP=10).OR.(GRADE=14.AND.STEP=7)
  NTUPLE/PLOT 10.GRADE STMASK(3)

Output of the command  MASK/LIST
STMASK     Events:   3354  (file stmask.mask, read/write)
            # select  Description
    bit  1:       41  step=15
    bit  2:      877  grade>4.and.step=13
    bit  3:       57  (grade=13.and.step=10).or.(grade=14.and.step=7)
    bit  4:      975  stmask(1).or.stmask(2).or.stmask(3)

A general macro to draw a legend
      Macro Legend
1     TYPE = [1]   | Type of hatches                                                           
1     X1   = [2]   | X bottom left corner of the box.                                          
1     X2   = [3]   | X top right corner of the box.                                            
1     Y1   = [4]   | Y bottom left corner of the box.                                          
1     Y2   = [5]   | Y top right corner of the box.                                            
1     TEXT = [6]   | Text to be printed                                                        
      Set FAIS 3
      Set FASI [TYPE]
      Set BORD 1
      Box [X1] [X2] [Y1] [Y2]
      Set TXAL 03
2     XT = [X2]+$GRAFINFO('?CHHE')                                                             
2     YT = ([Y2]+[Y1])/2                                                                       
2     Itx [XT] [YT] [TEXT]                                                                     
      Return

Input parameters 1 to 6 are copied into locale variables with meaningful names.
The text is positionned according to the text size and the box position.

			PAW Tutorial	Last update: 1999/04/01 14.59	Olivier.Couet@Cern.Ch