anchor.diff:  
   DOUBLE PRECISION, INTENT(IN) :: t
   
  -getcpc = 252.54 + 0.11474*t
  +getcpc = 252.54d0 + 0.11474d0*t
   
   END FUNCTION getcpc
   
  
positive.code: 
  DOUBLE PRECISION :: cvelo, Nu, Re
  
  cvelo = cflow / (farea * xden * 1000.)        ! Calculate flow velocity (m/s)
  Re = cvelo * dh / (kv * 1.d-6)                 ! Calculate Reynolds Number
  Nu = 0.023*(Pr**0.4)*(Re**0.8)                ! Calculate Nusselt Number
  geths = (tc / dh) * Nu                        ! Calculate heat transfer coefficient
  
  
  
negative.code: 
  DOUBLE PRECISION, INTENT(IN) :: t
  
  getkf = 1.05d0 + 2150.0d0 / (t - 73.15d0)
  
  END FUNCTION getkf
  
  