anchor.diff:  c
   c...  included dimension and type statements
   c
  +      include "nforce_dim.inc"
         include "nsysdat_dim.inc"
         include "npar_dim.inc"
         include "rtimdat_dim.inc"
  
positive.code:      &     ierr,errstrng)                                               ! errcode
          else
            call stress_drv(
       &     b,neq,                                                       ! force
       &     x,d,numnp,                                                   ! global
       &     dx,numslp,                                                   ! slip
       &     tfault,numfn,                                                ! fault
  
negative.code: c
          call fill(dcur,zero,ndof*numnp)
          call fill(dxcur,zero,ndof*numnp)
          call disp(dispvec,dcur,id,numnp,neq)
          if(numslp.ne.0) call disp(dispvec,dxcur,idx,numnp,neq)
  c
  c...rotate skewed coordinates to global system
  c
  