anchor.diff:  
   inletbc=2266.0_dp
   outletbc=666.7_dp
  -ptrans=5.33_dp
  -pleural_density=0.25_dp*0.1e-5_dp !kg/mm**3
   
   !!---------DESCRIPTION OF IMPORTANT PARAMETERS-----------
   !viscosity: fluid viscosity
  
positive.code:       else
  !Update vessel radii based on predicted pressures and then update resistance through tree
          call calc_press_area(grav_type,grav_vect,KOUNT,depvar_at_node,prq_solution,&
             mesh_dof,ptrans,vessel_type,elasticity_parameters,pleural_density)
          call calculate_resistance(viscosity,density,gamma)
  
  !Put the ladder stuff here --> See solve11.f
  
negative.code:      elasticity_parameters(2)=0.1_dp!this is a fraction of the radius so is unitless
       elasticity_parameters(3)=0.0_dp !Not used
  else
      print *, 'WARNING: Your chosen vessel type does not seem to be implemented assuming rigid'
      vessel_type='rigid'
      elasticity_parameters=0.0_dp
  endif
  
  if (mechanics_type.eq.'linear') then
      mechanics_parameters(1)=5.33_dp*98.07_dp !average transpulmonary pressure (Pa)
      mechanics_parameters(2)=0.25_dp*0.1e-5_dp !pleural density, defines gradient in pleural pressure (kg/mm**3)
  else
      print *, 'WARNING: Only linear mechanics models have been implemented to date,assuming default parameters'
          mechanics_parameters(1)=5.33_dp*98.07_dp !average transpulmonary pressure (Pa)
      mechanics_parameters(2)=0.25_dp*0.1e-5_dp !pleural density, defines gradient in pleural pressure (kg/mm**3)
  endif
  
  grav_dirn=2
  