%N pbval %F $MIR/src/subs/pb.for
%D Get the value of a primary beam.
%P rjs
%: image-data
%B
      real function pbval(pbObj,x,y)

      integer pbObj
      real x,y
  ---------------------------------------------------------------------
  Determine the value of the primary beam at a given location.

  Input:
    pbObj      Handle of the primary beam object.
    x,y        Grid location of the position of interest.
  Output:
    pbVal      Value of the primary beam.
