20011122: reading and writing a netcdf file

>From: "Devendra Singh" <address@hidden>
>Organization: ?
>Keywords: 200111220941.fAM9fqN08618 netCDF Fortran

Devendra,

>I have downloaded the netcdf files and generated a fortran template file for 
>reading my netcdf file. It has read all the variables correctly. I wish to 
>write the output in the following ascii format
>corrospoinding to each latitude and longitude , the temperature values of 
>all 42 pressure levels like
>
>lat  lon  pres_levels(1 to 42)
>
>up to end of file.
>
>format(2f8.2,42f7.2)
>
>I tried to do it but could not get through. I have done some modification 
>which start at line 255 and end at line 266. I could do the modification of 
>the two dimensional latitude and longitude into single dimension but could 
>not write the temperature values for all the pressure levels against these 
>lat/lon position.I am attaching the readnet.f fortran template file 
>alongwith netcdf file.  I request you to kindly insert one write statement 
>in the said routine for writing the output in the said format.

Typically, our support does not extend to helping users write
applications.  We simply do not have resources to provide that level of
service.  I was, however, interested in the data file that you were
trying to read (satellite retrievals).

Now, a couple of comments about your code:

1) you define ndims and nvars in PARAMETER statements at the beginning
   of readnet.f.  You then use these in an ncinq call:

      call ncinq(ncid,ndims,nvars,ngatts,recdim,rcode)

   The problem with this is that the second and third parameters to
   a ncinq call get filled with return values by ncinq:

FORTRAN Interface: NCINQ

               SUBROUTINE NCINQ(INTEGER NCID, INTEGER NDIMS, INTEGER NVARS,
              *                 INTEGER NGATTS, INTEGER RECDIM, INTEGER RCODE)

         NCID 
              NetCDF ID, returned from a previous call to NCOPN or NCCRE. 
         NDIMS 
              Returned number of dimensions defined for this netCDF file. 
         NVARS 
              Returned number of variables defined for this netCDF file. 
         NGATTS 
              Returned number of global attributes defined for this netCDF 
file. 
         RECDIM 
              Returned ID of the unlimited dimension, if there is one for this 
netCDF file. If
              no unlimited size dimension has been defined, -1 is returned for 
the value of
              RECDIM. 
         RCODE 
              Returned error code. If no errors occurred, 0 is returned.

   In standard Fortran, items declared in PARAMETER statements are not
   modifiable.  When attempting to run your code on a Solaris 2.6
   system using Sun's WS6 Fortran compiler, I get a core dump because
   of the use of items declared in PARAMETER statements in ncinq.

   The solution is to get rid of the PARAMETER declaration of nvars
   and change the ncinq call to use modifiable parameters:

      call ncinq(ncid,nndims,nvars,ngatts,recdim,rcode)

2) The write you want to make can be done with list directed write
   statements.  Here is one idea:

   your code:

      do i=1,Along_Track*Across_Track
      write(100,110)x(i),y(i)
      enddo
110   format(16x,7f8.2,/,16x,7f8.2,/,16x,7f8.2/,16x,7f8.2,
     1 /,16x,7f8.2/,16x,7f8.2,/)

   equivalent code:

      write(100,110) (x(i),y(i),i=1,Across_Track*Along_Track)
110   format(16x,2f8.2)


From your original format statement, it seems like you are wanting to
do something like:

c      do j=1,Along_Track
c      do i=1,Across_Track
c      k=(j-1)*Across_Track+i
c      x(k)=latitude(i,j)
c      y(k)=longitude(i,j)
c      enddo
c      enddo
c      do i=1,Along_Track*Across_Track
c      write(100,110)x(i),y(i)
c      enddo
c110   format(16x,7f8.2,/,16x,7f8.2,/,16x,7f8.2/,16x,7f8.2,
c     1 /,16x,7f8.2/,16x,7f8.2,/)

      do j = 1, Along_Track
        do i = 1, Across_Track
          write(100,110)
     &    latitude(i,j),longitude(i,j),(Temperature_Retrieval(i,k,j),
     &    k=1,Pres_Levels)
        enddo
      enddo
110   format(2f8.2,42f7.2)

>with kindest regards,
>Devendra Singh

Tom Yoksas