subroutine aptst(icx,kode)
c
c this subroutine tests the data to select specific
c aperture bias voltage value data selected in the
c subrouitne apset. if kode=0 there is data in the
c required aperture bias range,and if kode=-1 there
c is no data in the specified range.
c
c ic(1)=idat(138)=aperture voltage monitor value for 1st sec
c ic(2)=idat(250)=ap. vol. mon. value for 8th of 8 sec in record
c icx=aperture bias specification from apset
c kode=return code :0=data,-1=no data
c
c jhwjr 26 oct.,82 subroutine written
c
      byte icx,ich,ichrs(4),ia
      integer ic(2),ilims(2,4),idat(2812)
      common /maf1/idat
      data ilims/0,5,45,55,95,105,195,205/
      data ichrs/'0','2','4','8'/
      data ia/'a'/

      ic(1)=idat(138)
      ic(2)=idat(250)
      kode=0
      ich='x'
      if(icx.eq.ia) return
      do 100 j=1,2
         do 50 i=1,4
            if(ic(j).ge.ilims(1,i).and.ic(j).le.ilims(2,i)) ich=ichrs(i)
   50    continue
         if(ich.ne.icx) kode=-1
  100 continue
c     write(6,10) ic(1),ic(2),icx,ich,kode
c 10  format(' aptst',2i4,2a2,i3)
      return
      end