source/unres/src_MD-M-SAXS.safe/b

   1 C Calculate the distance between the two points and its difference from the
   2 C target distance.
   3           dd=dist(ii,jj)
   4           write (iout,*) "ELSE: dd",dd," constr_dist",constr_dist
   5           if (constr_dist.eq.11) then
   6             ehpb=ehpb+fordepth(i)!**4.0d0
   7      &           *rlornmr1(dd,dhpb(i),dhpb1(i),forcon(i))
   8             fac=fordepth(i)!**4.0d0
   9      &           *rlornmr1prim(dd,dhpb(i),dhpb1(i),forcon(i))/dd
  10             if(energy_dec)write (iout,'(a6,2i5,6f10.3)') "edisl",ii,jj,
  11      &        dd,dhpb(i),dhpb1(i),forcon(i),fordepth(i),ehpb
  12           else if (constr_dist.eq.10) then
  13 c AL 6//19/2018 cross-link restraints
  14             xdis = (dd/forcon(i))**2
  15             write (iout,*) "HERE: xdis",xdis
  16             expon = dexp(-xx)
  17             aux=(dhpb(i)+dhpb1(i)*xx)*expon+fordepth(i)
  18             ehpb=ehpb-wboltzd*dlog(aux)
  19             fac=-wboltzd*dhpb1(i)*(1.0d0-xx)*dxpon/(aux*forcon(i)**2)
  20             if (energy_dec)write(iout,'(a6,2i5,6f10.3)') "edisl",ii,jj,
  21      &        dd,dhpb(i),dhpb1(i),forcon(i),fordepth(i),ehpb
  22           else
  23 c Quadratic or quartic  restraints
  24             if (dhpb1(i).gt.0.0d0) then
  25               ehpb=ehpb+2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
  26               fac=forcon(i)*gnmr1prim(dd,dhpb(i),dhpb1(i))/dd
  27 c             write (iout,*) "alph nmr",
  28 c     &       dd,2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
  29             else
  30               rdis=dd-dhpb(i)
  31 C Get the force constant corresponding to this distance.
  32               waga=forcon(i)
  33 C Calculate the contribution to energy.
  34               ehpb=ehpb+waga*rdis*rdis
  35 c            write (iout,*) "alpha reg",dd,waga*rdis*rdis
  36 C
  37 C Evaluate gradient.
  38 C
  39               fac=waga*rdis/dd
  40             endif
  41           endif
  42 c Calculate Cartesian gradient
  43           do j=1,3
  44             ggg(j)=fac*(c(j,jj)-c(j,ii))
  45           enddo
  46 cd      print '(i3,3(1pe14.5))',i,(ggg(j),j=1,3)
  47 C If this is a SC-SC distance, we need to calculate the contributions to the
  48 C Cartesian gradient in the SC vectors (ghpbx).
  49           if (iii.lt.ii) then
  50             do j=1,3
  51               ghpbx(j,iii)=ghpbx(j,iii)-ggg(j)
  52               ghpbx(j,jjj)=ghpbx(j,jjj)+ggg(j)
  53             enddo
  54           endif
  55 cgrad        do j=iii,jjj-1
  56 cgrad          do k=1,3
  57 cgrad            ghpbc(k,j)=ghpbc(k,j)+ggg(k)
  58 cgrad          enddo
  59 cgrad        enddo
  60           do k=1,3
  61             ghpbc(k,jjj)=ghpbc(k,jjj)+ggg(k)
  62             ghpbc(k,iii)=ghpbc(k,iii)-ggg(k)
  63           enddo
  64         endif
  65