%N antind %F $MIR/src/subs/antennas.for
%D Get index of an antenna pair
%: baselines, antenna
%B
      subroutine antind (maxant, a1, a2, idx)

      implicit none
      integer maxant, a1, a2, idx

     Compute the pointer to the logical baseline mask for a pair
     of antennas.

   Input:
     maxant Maximum number of antennas allowed
     a1     First antenna
     a2     Second antenna
   Output:
     idx  Pointer
