anchor.diff:  c~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   c
   c
  -      subroutine iterate(alnz,pcg,zcg,ja,                               ! sparse
  -     & b,btot,bres,pvec,gvec1,gvec2,                                    ! force
  -     & x,d,dx,deld,deldx,dprev,dcur,dxcur,id,idx,skew,histry,           ! global
  -     & ien,infin,mat,lm,lmx,lmf,prop,gauss,                             ! elemnt
  -     & dmat,stn,scur,st0,eps,deps,beta,dbeta,betb,dbetb,iddmat,         ! stress
  +      subroutine iterate(
  +     & alnz,pcg,zcg,ja,                                                 ! sparse
  +     & b,btot,bres,pvec,gvec1,gvec2,grav,                               ! force
  +     & x,d,deld,dprev,dcur,id,iwink,wink,nsysdat,                       ! global
  +     & dx,deldx,dxcur,idx,iwinkx,winkx,idslp,ipslp,                     ! slip
  +     & nfault,dfault,tfault,                                            ! fault
  +     & s,stemp,                                                         ! stiff
  +     & state,dstate,dmat,ien,lm,lmx,lmf,infiel,iddmat,npar,             ! elemnt
        & ielno,iside,ihistry,pres,pdir,                                   ! tractn
  -     & nfault,dfault,tfault,                                            ! split
  -     & idslp,ipslp,                                                     ! slip
  -     & iwink,wink,iwinkx,winkx,                                         ! wink
  -     & s,stemp,                                                         ! local
  -     & gcurr,gi,gprev,grav,gtol,ncodat,ndimens,                         ! info
  -     & npar,nprint,nsiter,nsysdat,ntimdat,nunits,nvisdat,rgiter,        ! info
  -     & rmin,rmult,rtimdat)                                              ! info
  +     & prop,mhist,infmat,                                               ! materl
  +     & gauss,sh,shj,infetype,                                           ! eltype
  +     & histry,rtimdat,ntimdat,nvisdat,                                  ! timdat
  +     & rgiter,gcurr,gi,gprev,gtol,rmin,rmult,nsiter,                    ! iterate
  +     & skew,                                                            ! skew
  +     & ncodat,nunits,nprint,                                            ! ioinfo
  +     & getshape,bmatrix,gload_cmp,stress_cmp,stress_mat_cmp,            ! external
  +     & ierr,errstrng)                                                   ! errcode
   c
   c...subroutine to loop over iterations within each time step
   c
  
positive.code:      &   gcurr,gprev,ja,nsiter,neq,nnz,ndtot,idout,kto,kw,used)
          ntimdat(9)=ndtot
          if(nsol.eq.2.or.nsol.eq.4) then
            if(i.eq.1) call fill(dprev,zero,neq)
            call daxpy(neq,one,gvec2,ione,dprev,ione)
          end if
  c
  c...for first iteration, update displacements to reflect boundary
  c   conditions
  c
          if(i.eq.1) then
            if(numfn.ne.0.and.numrot.ne.0) call rsplit(nfault,dfault,
       &     skew,ndof,numfn,numnp,nskdim)
            if(numfn.ne.0) call daxpy(ndof*numfn,one,dfault,ione,tfault,
       &     ione)
            if(nstep.eq.0) then
              if(numrot.ne.0) call rdisp(dcur,skew,ndof,numnp,nskdim)
              call dcopy(ndof*numnp,dcur,ione,d,ione)
              call dcopy(ndof*numnp,dcur,ione,deld,ione)
            else
              if(numrot.ne.0) call rdisp(deld,skew,ndof,numnp,nskdim)
              call daxpy(ndof*numnp,one,deld,ione,d,ione)
            end if
          end if
  
negative.code: c
  c...  local variables
  c
        integer i,iter
        logical fulout,converge,updats,skc,used,reform
  c
  c...  included variable definitions
  c
        include "nsysdat_def.inc"
        include "npar_def.inc"
        include "rtimdat_def.inc"
        include "ntimdat_def.inc"
        include "nvisdat_def.inc"
        include "rgiter_def.inc"
        include "nsiter_def.inc"
        include "ncodat_def.inc"
        include "nunits_def.inc"
        include "nprint_def.inc"
  c
  c...initialize convergence criteria
  c
  cdebug      write(6,*) "Hello from iterate_f!"
  c
        fulout=.true.
        converge=.false.
  