anchor.diff:  ,,,,,,
   ,,,,,,
   "265.  ","Rock (Average of 5 types)",,,,,
  -"Formula =","-",,"Molecular mass (g/mole) =","Molecular mass (g/mole) =",,"-"
  +"Formula =","-",,"Molecular weight (g/mole) =","Molecular weight (g/mole) =",,"-"
   "Density (g/cm3) =",,2.662000,"Total atom density (atoms/b-cm) =",,,8.028E-02
   "The above density is estimated to be accurate to 3 significant digits.  Dealing with uncertainties is left to the user.",,,,,,
  -"The following data was calculated from the input mass fractions.",,,,,,
  -,,,,,,
  -,,,"Mass","Atom","Atom",
  +"The following data was calculated from the input weight fractions.",,,,,,
  +,,,,,,
  +,,,"Weight","Atom","Atom",
   "Element","Neutron ZA","Photon ZA","Fraction","Fraction","Density",
   "H",1001,1000,0.001657,0.032837,0.002636,
   "C",6000,6000,0.026906,0.044735,0.003591,
  
positive.code: ,,,,,,
  "Total",,,1.000000,1.000000,0.117467,
  ,,,,,,
  "MCNP Form","Mass Fractions",,"Atom Fractions",,"Atom Densities",
  "Neutrons",1001,-0.052859,1001,0.465116,1001,0.054636
  ,"-",-0.113391,"-",0.093023,"-",0.010927
  ,8016,-0.713187,8016,0.395349,8016,0.046441
  
negative.code: ,,,,,,
  "Total",,,1.000000,1.000000,0.103624,
  ,,,,,,
  "MCNP Form","Weight Fractions",,"Atom Fractions",,"Atom Densities",
  "Neutrons",1001,-0.027227,1001,0.285714,1001,0.029607
  ,6000,-0.162222,6000,0.142857,6000,0.014803
  ,7014,-0.378361,7014,0.285714,7014,0.029607
  