anchor.diff:        subroutine ridge_tag4refinement(mx,my,mbc,meqn,
  -     &      xlower,ylower, dx,dy,q,maux,aux,initflag,tag_patch)
  +     &      xlower,ylower, dx,dy,q,level,maux,aux,initflag,tag_patch)
         implicit none
   
         integer mx,my, mbc, meqn, tag_patch, initflag, maux
  +      integer level
         double precision xlower, ylower, dx, dy
         double precision q(1-mbc:mx+mbc,1-mbc:my+mbc,meqn)
         double precision aux(1-mbc:mx+mbc,1-mbc:my+mbc,maux)
  
positive.code: 
  c     # We tag for coarsening if this coarsened patch isn't tagged for refinement
        subroutine ridge_tag4coarsening(mx,my,mbc,meqn,
       &      xlower,ylower,dx,dy,qcoarsened, maux,aux,initflag,tag_patch)
        implicit none
  
        integer mx,my, mbc, meqn, tag_patch, maux, initflag
        double precision xlower, ylower, dx, dy
        double precision qcoarsened(1-mbc:mx+mbc,1-mbc:my+mbc,meqn)
        double precision aux(1-mbc:mx+mbc,1-mbc:my+mbc,maux)
  
negative.code:       tag_patch = 0
        do i = 1,mx
           do j = 1,my
              eta = q(i,j,1) + aux(i,j,19)
              if (abs(eta) .gt. tol1 .or.
       &            (abs(eta) .gt. tol1 .and. level .gt. 0)) then
                 tag_patch = 1
                 return
              endif
           enddo
        enddo
  
  