function function_of_pstar_PT(sgnBC,Pstar,Rotank,Ctank,Ptank,Einttank,p_LR,u_LR,z_LR)
real(dp), intent(in) :: sgnBC,Pstar,Rotank,Ctank,Ptank,Einttank,p_LR,u_LR,z_LR
real(dp) :: function_of_pstar_PT, ustar, rostar_LR, Tstar_LR, R_Corr_star_LR, estar_LR, Cstar_LR
rostar_LR=Rotank+(Pstar-Ptank)/(Ctank**2)
Ustar=u_LR+sgnBC*(Pstar-p_LR)/z_LR
call state_roP(rostar_LR, Pstar, R_Corr_star_LR, estar_LR, Tstar_LR, Cstar_LR)
function_of_pstar_PT=estar_LR+Pstar/rostar_LR+0.5_dp*(ustar**2)-Einttank-Ptank/Rotank
end function function_of_pstar_PT