c---------------------------------------------------------------------
c---------------------------------------------------------------------

      subroutine exact_solution(xi,eta,zeta,dtemp)

c---------------------------------------------------------------------
c---------------------------------------------------------------------

c---------------------------------------------------------------------
c     this function returns the exact solution at point xi, eta, zeta  
c---------------------------------------------------------------------

      include 'header.h'

      double precision  xi, eta, zeta, dtemp(5)
      integer m

      do m = 1, 5
         dtemp(m) =  ce(m,1) +
     >     xi*(ce(m,2) + xi*(ce(m,5) + xi*(ce(m,8) + xi*ce(m,11)))) +
     >     eta*(ce(m,3) + eta*(ce(m,6) + eta*(ce(m,9) + eta*ce(m,12))))+
     >     zeta*(ce(m,4) + zeta*(ce(m,7) + zeta*(ce(m,10) + 
     >     zeta*ce(m,13))))
      enddo

      return
      end