anchor.diff:  c        iprint=99   print details of every iteration except n-vectors;
   c        iprint=100  print also the changes of active set and final x;
   c        iprint>100  print details of every iteration including x and g;
  -c       When iprint > 0, the file iterate.dat will be created to
  -c                        summarize the iteration.
  +c       
   c
   c     csave is a working string of characters of length 60.
   c
  
positive.code: c        iprint=99   print details of every iteration except n-vectors;
  c        iprint=100  print also the changes of active set and final x;
  c        iprint>100  print details of every iteration including x and g;
  c       When iprint > 0, the file iterate.dat will be created to
  c                        summarize the iteration.
  c
  c     csave is a working string of characters of length 60.
  c
  
negative.code:   
        if (iprint .ge. 1) then
           write (6,1002) iter,f,sbgnrm
        endif
        if (sbgnrm .le. pgtol) then
  c                                terminate the algorithm.
  