anchor.diff:        subroutine limiter(maxm,meqn,mwaves,mbc,mx,wave,s,mthlim)
   c     =====================================================
   c
  -c     # Apply a limiter to the waves.  
  +c     # Apply a limiter to the waves.
   c
   c     # Version of December, 2002.
  -c     # Modified from the original CLAWPACK routine to eliminate calls 
  +c     # Modified from the original CLAWPACK routine to eliminate calls
   c     # to philim.  Since philim was called for every wave at each cell
   c     # interface, this was adding substantial overhead in some cases.
   c
   c     # The limiter is computed by comparing the 2-norm of each wave with
   c     # the projection of the wave from the interface to the left or
   c     # right onto the current wave.  For a linear system this would
  -c     # correspond to comparing the norms of the two waves.  For a 
  -c     # nonlinear problem the eigenvectors are not colinear and so the 
  +c     # correspond to comparing the norms of the two waves.  For a
  +c     # nonlinear problem the eigenvectors are not colinear and so the
   c     # projection is needed to provide more limiting in the case where the
   c     # neighboring wave has large norm but points in a different direction
   c     # in phase space.
  
positive.code: c     # given by dotl/wnorm2 and dotr/wnorm2, where wnorm2 is the 2-norm
  c     # of wave.
  c
        implicit double precision (a-h,o-z)
        dimension mthlim(mwaves)
        dimension wave(meqn, mwaves, 1-mbc:maxm+mbc)
        dimension    s(mwaves, 1-mbc:maxm+mbc)
  c
  c
        do 200 mw=1,mwaves
           if (mthlim(mw) .eq. 0) go to 200
  
negative.code:                wnorm2 = wnorm2 + wave(m,mw,i)**2
                 dotr = dotr + wave(m,mw,i)*wave(m,mw,i+1)
      5          continue
              if (i .eq. 0) go to 190
              if (wnorm2 .eq. 0.d0) go to 190
  c
              if (s(mw,i) .gt. 0.d0) then
                  r = dotl / wnorm2
  