subroutine dali(x,arg,val,y) * * four-point lagrange interpolation via interpolating polynomial. * implicit double precision(a-h,o-z) dimension arg(1),val(1) do 6 j=2,4 iend=j-1 do 2 i=1,iend h=arg(i)-arg(j) val(j)=(val(i)*(x-arg(j))-val(j)*(x-arg(i)))/h 2 continue 6 continue y=val(4) return end ************************************************************************