anchor.diff:  c~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   c
   c
  -      subroutine presurql(pres,pdir,xl,p,ien,iside,infin,n,nen,nsd,
  -     & ndof,npdir,idout,kto,kw)
  +      subroutine presurql(pres,pdir,xl,p,ien,iside,infin,n,nen,
  +     & idout,kto,kw)
   c
   c...subroutine to compute local load vector for traction BC
   c
  
positive.code: c
        include "implicit.inc"
  c
  c...  subroutine arguments
  c
        integer iside,infin,n,nen,nsd,ndof,npdir,idout,kto,kw
        integer ien(nen)
        double precision pres(nen/2),pdir(npdir),xl(nsd,nen),p(ndof,nen)
  c
  
negative.code:         rgs(1)=rf(iiside)+ri(iiside)*g*rg(ipnt)
          rgs(2)=sf(iiside)+si(iiside)*g*sg(ipnt)
          rgs(3)=tf(iiside)+ti(iiside)*g*tg(ipnt)
          call shapql(rgs,xl,det,sh,ien,nen,infin,iopt,n,idout,kto,kw)
  c
  c...  compute surface element for use in integration
  c
  