%N teken %F $MIR/src/subs/utilities.for
%D Returns the sign of a real value
%P bpw
%: utilities
%B
     integer          function tekeni ( i )
     real             function tekenr ( r )
     double precision function tekend ( d )
     integer          i
     real             r
     double precision d

 tekenr returns +1.   or -1.   depending on the sign of the real x.
 tekeni returns +1    or -1    depending on the sign of the integer i
 tekend returns +1.d0 or -1.d0 depending on the sign of the double
                               precision variable d
