program info_GSFC 

      implicit real*8 (a-h,o-z)
      logical in_sol,in_sol1,isdata,pseudo,rad,first
      integer*2 year
      dimension time(2),rlat(2),rlon(2),u(3,2),v(3,2)

      COMMON /TEST/ YEAR,FIRST,FACT(11),TICON(11)

      data FACT /11*1.d0/

c...Read sample input data file to get time and position. 
c    rlat - north latitude (in degrees, -90 to  90)
c    rlon - east longitude (in degrees,  0  to 360)
c    time - desired time,  Modified Julian Date in days. e.g.,
c     Jan 1, 1992 is 48622.

      rlat(1) = -65.44040
      rlon(1) = 277.80185
      time(1) = 49354.41959

      rlat(2) = -63.10150
      rlon(2) = 291.97490
      time(2) = 49354.50178

      do i = 1,2

c...Call the Schwiderski and GSFC model to compute the tide height
c       in_sol - logical denoting whether tide data exists
c                at desired location
c       tpd    - ocean tide + long period tide height in cm
c       tlp    - long period tide height in cm
c       tocean - ocean tide height in cm
c       tod    - loading tide in cm        
c       tide   - predicted ocean tide in cm

      call schwid(time(i),rlat(i),rlon(i),tpd,tlp,tocean,in_sol)

c...Compute the loading tide height
       call tptide (rlat(i),rlon(i),time(i)*86400.d0,tod,isdata,
     &    u,v,pseudo,rad)

c...Compute the tidal correction by GSFC model
c      tcorr  - tidal height correction in cm

       sday = REAL(INT(time(i)))
       sfra = time(i) - sday
       call ctide (rlat(i),rlon(i),sday, sfra,isdata,tcorr)

       tide = tpd + tod + tcorr

      if (in_sol) then
        write(6,*) rlat(i),rlon(i),time(i),tide,tpd,tod,tcorr
      else
        write(6,*) 'No tide solution avaliable.'
      endif

      enddo

      stop
      end 

c...The output data is:
c   -65.44040, 277.80185, 49354.41959, 23.66801, 21.86176, -1.90456, 3.71089
c   -63.10150, 291.97490, 49354.50178, 43.72160, 40.45293,  4.47888 -1.21021


c  GSFC94A
c  -------
c       The  GSFC94A  model  [Sanchez  and  Pavlis,  1995]  is  based  on
c  corrections  to  the  Schwiderski  model for four diurnal (!Q1!, !P1!,
c  !O1! and !K1!) and  four  semidiurnal  (!M2!,  !S2!,  !N2!  and  !K2!)
c  constituents.   Residual  sea  surface  heights  remaining  after  the
c  Schwiderski correction from the first 40 cycles of JGM-2  orbit  TOPEX
c  data  were  parameterized in terms of a set of Proudman functions. The
c  solutions from these fits were then used  to  compute  a  new  overall
c  model  on  a  !2^times^2!   degree  grid  within 76.75  S to 69.25  N.
c  Owing to the large grid-size  and  the  limitations  of  the  Proudman
c  function  approach  in  shallow  waters, the GSFC94A model results are
c  valid only in the deep ocean.