C =======
C COMMON.DFA
C =======
C 2010/12/20 By Juyong Lee
C
c parameter
C [ 8 * ( Nres - 8 ) ] distance restraints 
C [ 2 * ( Nres - 8 ) ] angle restraints
C [ Nres ]             neighbor restraints
C Total : ~ 11 * Nres restraints
C
C
      INTEGER IDFAMAX,IDFAMX2,IDFACMD,IDMAXMIN, MAXN
      PARAMETER(IDFAMAX=4000,IDFAMX2=1000,IDFACMD=500,IDMAXMIN=500)
      PARAMETER(MAXN=4)
      real*8 wwdist,wwangle,wwnei
      parameter(wwdist=1.0d0,wwangle=1.0d0,wwnei=1.0d0)

C IDFAMAX  - maximum number of DFA restraint including distance, angle and
C            number of neighbors ( Max of assign statement )
C IDFAMX2  - maximum number of atoms which are targets of restraints
C IDFACMD  - maximum number of 'DFA' command call
C IDMAXMIN - Maximum number of minima of dist, angle and neighbor info. from fragments
C MAXN     - Maximum Number of shell, currently 4
C MAXRES   - Maximum number of CAs

CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCc
C INTEGER 
C DFANUM  - Number of ALL DFA restrants
c IDFA[DIS, PHI, THE, NEI] - NUMBER of restraints
c IDISNUM - number of minima for a distance restraint
c IPHINUM - number of minima for a phi angle restraint
c ITHENUM - number of minima for a theta angle restraint
c INEINUM - number of minima for a number of neighbors restraint

c IDISLIS - atom number of two atoms for distance restraint
c IPHILIS - atom numbers of four atoms for angle restraint
c ITHELIS - atom numbers of four atoms for angle restraint
c INEILIS - atom number of center of neighbor calculation
c JNEILIS - atom number of target of neighboring calculation
c JNEINUM - number of target atoms of neighboring term
C KSHELL  - SHELL number 

C ishiftca - index shift for CA atoms in UNRES (1 if the 1st aa != GLY)
C ilastca  - index of the last CA atom in UNRES (nres-1 if last aa != GLY)

C     old only for CHARMM
C STOAGDF - Store assign information ( How many assign within one command )
C NMAP    - mapping between dfanum and ndis, nphi, nthe, nnei

      INTEGER IDFADIS,IDFAPHI,IDFATHE,IDFANEI,
     & 	      IDISLIS,IPHILIS,ITHELIS,INEILIS,
     &        IDISNUM,IPHINUM,ITHENUM,INEINUM,
     &        FNEI,
     &        NCA,ICAIDX,
     &        STOAGDF, NMAP, IDFACAT, KDISNUM, KSHELL
     &        ishiftca,ilastca 
      COMMON /IDFA/ DFACMD, DFANUM,
     &              IDFADIS, IDFAPHI, IDFANEI, IDFATHE, 
     &              IDISNUM(IDFAMAX), IPHINUM(IDFAMAX), 
     &              ITHENUM(IDFAMAX), INEINUM(IDFAMAX),
     &              FNEI(IDFAMAX,IDMAXMIN), IDISLIS(2,IDFAMAX),
     &              IPHILIS(5,IDFAMAX), ITHELIS(5,IDFAMAX),
     &              INEILIS(IDFAMAX),
     &               KSHELL(IDFAMAX),
     &              IDFACAT(IDFACMD),
     &              KDISNUM(IDFAMAX),
     &              NCA, ICAIDX(MAXRES)
      COMMON /IDFA2/ ishiftca,ilastca

CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
C
C REAL VARIABLES
C
c SCC[DIST, PHI, THE] - weight of each calculations
c FDIST  - distance minima
C FPHI   - phi minima
c FTHE   - theta minima
C DFAEXP  : calculate expential function in advance
C
      REAL*8 SCCDIST, SCCPHI, SCCTHE, SCCNEI, FDIST, FPHI1, FPHI2,
     &       FTHE1, FTHE2,
     &       DIS_INC, PHI_INC, THE_INC, NEI_INC, BETA_INC,
     &       WSHET, EDFABET, 
     &       CK, SCK
c    &       ,DFAEXP

      COMMON /RDFA/ SCCDIST(IDFAMAX,IDMAXMIN),FDIST(IDFAMAX,IDMAXMIN),
     &             SCCPHI(IDFAMAX,IDMAXMIN), SCCTHE(IDFAMAX,IDMAXMIN), 
     &             SCCNEI(IDFAMAX,IDMAXMIN),
     &             FPHI1(IDFAMAX,IDMAXMIN), FPHI2(IDFAMAX,IDMAXMIN),
     &             FTHE1(IDFAMAX,IDMAXMIN), FTHE2(IDFAMAX,IDMAXMIN), 
     &             DIS_INC, PHI_INC, THE_INC, NEI_INC, BETA_INC,
     &             WSHET(MAXRES,MAXRES), EDFABET, 
     &             CK(4),SCK(4),S1(4),S2(4)
c    &             ,DFAEXP(15001),

      DATA CK/1.0D0,1.58740105197D0,2.08008382305D0,2.51984209979D0/
      DATA SCK/1.0D0,1.25992104989D0,1.44224957031D0,1.58740105197D0/
      DATA S1/3.75D0,5.75D0,7.75D0,9.75D0/
      DATA S2/4.25D0,6.25D0,8.25D0,10.25D0/