subroutine eint(t,e1,e2,e3)
c     ============================
c
c  returns the values of the exponential integral function of order
c  1, 2, and 3
c
c     a modification of Tim Kallman's XSTAR routine
c
      INCLUDE 'IMPLIC.FOR'
       e1=0.
       e2=0.
       e3=0.
       call expinx(t,ss)
       e1=ss/t/expo(t)
       e2=exp(-t)-t*e1
       e3=0.5*(expo(-t)-t*e2)
       return
       end