EPSILON — Epsilon functionEPSILON(X) returns the smallest number E of the same kind
as X such that 1 + E > 1.
     RESULT = EPSILON(X)
     | X | The type shall be REAL. | 
          program test_epsilon
              real :: x = 3.143
              real(8) :: y = 2.33
              print *, EPSILON(x)
              print *, EPSILON(y)
          end program test_epsilon