subroutine rdzen(nopr,iout,&
  num,numqf0,numqf1,lons,lats,&
  zensun,zensensor,azsun,azsensor,&
  phidiffs)
 
! *****
  integer, parameter :: numlatmax=100
  integer :: idat,nopr,iout,num,i,j
  character(len=80) :: header

! see rdzen.f90 for Lite file averages
  integer :: numqf0(numlatmax),numqf1(numlatmax)
  real :: lons(numlatmax),lats(numlatmax)
  real :: zensun(numlatmax),zensensor(numlatmax)
  real :: azsun(numlatmax),azsensor(numlatmax)
  real :: phidiffs(numlatmax)

! *****
! First couple lines of task310.dat
! task310: num
!   16
! task310: fileone
! /ur/massie/oco2_pattern/task300/litefiles/oco2_LtCO2_200612_B11014Ar_220902223013s.nc4
! task310: i,numqf0(i),numqf1(i),lons(i),lats(i),zensun(i),zensensor(i),azsun(i),azsensor(i),phidiffs(i)
!   1    8   20  -137.0095    25.1448    17.1009    13.5284   267.4379
! 88.2799  -179.1580
!   2  325   88  -136.3994    22.7877    17.6318    13.9234   275.0064
! 96.0922  -178.9142

! *****
! Output ascii file f.out
   idat=10
  open(idat,form='formatted',file='task310.dat',status='unknown')

! *****
! Read in the data
  read(idat,fmt=100) header
  read(idat,*) num
  read(idat,fmt=100) header
  read(idat,fmt=100) header
  read(idat,fmt=100) header
  100 format(a80)

  do i=1,num
   read(idat,fmt=200) j,numqf0(i),numqf1(i),lons(i),lats(i),&
   zensun(i),zensensor(i),azsun(i),azsensor(i),phidiffs(i)
  enddo
  200 format(2x,i3,2(1x,i4),7(1x,f10.4))

! *****
! close the input data file
  close (idat)

! *****
! Write out input data to tyhe f.out ascii file
  if (nopr .eq. 1) then
    write(iout,fmt=300)
    300 format(/,2x,"rdzen:  i,numqf0(i),numqf1(i),lons(i),lats(i),",/,&
    2x,"zensun(i),zensensor(i),azsun(i),azsensor(i),phidiffs(i)")
   do i=1,num
    phidiffs(i)=abs(azsun(i)-azsensor(i))
    write(iout,fmt=200) i,numqf0(i),numqf1(i),lons(i),lats(i),&
    zensun(i),zensensor(i),azsun(i),azsensor(i),phidiffs(i)
   end do
  end if

! *****
  return
  end