*-- Author :    I.O.Skillicorn
      SUBROUTINE FTVDET
C     DRIFT VELOCITY DETERMINATION PER TRACK FOR RADIALS                                                      
*KEEP,FRDIMS.                                                                                                 
*KEEP,FH1WORK.                                                                                                
*    Planar geometry                                                                                          
*                                                                                                             
*    Radial geometry                                                                                          
*                                                                                                             
*    Radial data...                                                                                           
*                                                                                                             
*    Planar Data                                                                                              
*                                                                                                             
*    Pointers into DIGI bank for IOS labelled hits                                                            
*                                                                                                             
*    Track segment data                                                                                       
*                                                                                                             
*    Fit data                                                                                                 
*                                                                                                             
*                                                                                                             
*KEEP,FPTVTX.                                                                                                 
**the common/VERTEX/ becomes /VERTVV/ (in analogy to /VERTFF/) on the                                         
** 17/6/91, since it is in conflict with the VERTEX module (g.bernardi)                                       
** (note that all these common names should start by F in this deck...)                                       
*KEEP,FRH3FT.                                                                                                 
*     Common for RETRAC results (SJM)                                                                         
*KEEP,FPPRAM.                                                                                                 
C                                                                                                             
C---  MAXSEG is maximum number of segments per supermodule                                                    
C---  MAXCON is maximum number of amibiguous segments associatable with                                       
C---         one segment                                                                                      
C---  LIMSTO is maximum number of 2 cluster planes intersections to be                                        
C---         stored per supermodule                                                                           
C---  MSEGLM is maximum number of clusters that can be found before                                           
C---         connectivity considered                                                                          
C---  MAXCLU is maximum number of clusters that can be found after                                            
C---         forming non-connected set    MUST BE 50 IF RUN WITH OLD RCW                                      
C---         (cluster = 3/4 digits found in a straight line in one                                            
C---          4-wire orientation)                                                                             
C                                                                                                             
C---                                                                                                          
*KEEP,FPLSEG.                                                                                                 
C---                                                                                                          
C---                                                                                                          
*KEEP,FPTFLG.                                                                                                 
*KEEP,FPTPAR.                                                                                                 
*KEEP,FDIFLG.                                                                                                 
*KEND.                                                                                                        
*     Common for track parameter errors...                                                                    
*     Common for segment numbers...                                                                           
*     COMMON FOR PLANAR PATREC  ...                                                                           
C     POINTER TO RADIAL ASSOCIATED WITH NPP'TH PLANAR                                                         
C     COMMON FOR RADIALS ASSOCIATED WITH PLANAR TRACKS                                                        
*     Local arrays...                                                                                         
C     CHECK WHICH PLANAR MODULES ARE FOUND                                                                    
C     CHECK RADIAL BETWEEN PLANAR SEGMENTS                                                                    
C       CALL SHS(704+ISM,0.,DRE-DRMM)                                                                         
C       CALL SHS(704+ISM,0.,DRE-DRMM)                                                                         
C       IF(IP2.EQ.1.AND.IP3.EQ.1.AND.ISM.EQ.3)THEN                                                            
C       CALL SHS(704+ISM,0.,DRE-DRMM)                                                                         
C       SEE=DRE*DRE                                                                                           
C       SME=DRMM*DRE                                                                                          
C       SSS=SSS+1.0                                                                                           
C       ENDIF                                                                                                 
C     CALCULATE VELOCITY CORRECTION                                                                           
      CALL SHS(761,0,VFAC)                                                                             
      CALL SHS(762,0,TZ  )                                                                             
*