How to Build and Install the Radtran C and Fortran Libraries and Associated Tools
================================================================================= 

   Building of libRadtran is relatively simple. Prior to
building you may want to download additional software to build a
libRadtran with all options envoked. Usually libRadtran also requires
several GNU tools to be installed already. What you need and how to
get it is specified below. 

   To unpack, configure and build libRadtran is a simple three step
process:

   1. To unpack either do (power users)

        tar -xzvf libRadtran-version_number.tar.gz

      or struggle with poor man's tar

        gzip -d libRadtran-version_number.tar.gz
        tar -xvf  libRadtran-version_number.tar

   2. Configure libRadtran for your system (if you want to install
      the package in a place different from `/usr/local` use the 
      --prefix=PATH option to configure).   

        cd libRadtran-version_number
        ./configure

   3. Compile and link the thing

        make

After a succesful build you may want to test some of the tools coming
with libRadtran. Try

        make check

To install the executables, data files and documentation type
       
        make install

This will install the package's file in 
`/usr/local/bin`                      # uvspec and other tools
`/usr/local/include/libRadtran`       # include files
`/usr/local/lib`                      # libRadtran_c and libRadtran_f
`/usr/local/share/libRadtran/doc`     # all libRadtran documentation
`/usr/local/share/libRadtran/examples # all libRadtran example input and output files
`/usr/local/share/libRadtran/data`    # all libRadtran data files

You can specify an installation prefix other than `/usr/local' by
giving `configure' the option `--prefix=PATH'. 

In order to have uvspec recognize the whereabouts of the libRadtran
datafiles you have to specify the location of the datafiles using the
environment variable LIBRADTRAN_DATA_FILES. For the Bourne again shell
(bash) this is done by the following command:

        export LIBRADTRAN_DATA_FILES=/usr/local/share/libRadtran/data/

if you install in the standard location /usr/local. If you use any
other location you have to specify the location accordingly.

To uninstall try:
   
         make uninstall




Additional stuff to get a complete libRadtran
=============================================

   LibRadtran will build and the tools will run nicely without the
below software. However, some of us have special needs and must have
these options included as well. If you do not recognize what we are
talking about below, you probably do not need it and may happily
ignore it. 

   * To include the correlated-k stuff of Kato et al. libnetcdf is
     needed. Two options exist to include it.
      -You have a nice sysadm who has already put it on your
       system. If so it will be detected during the configuration
       process and automagically included.
      -You have to get it yourself from
       http://www.unidata.ucar.edu/packages/netcdf/index.html
       and build it yourself. To tell configure where you put
       libnetcdf invoke configure as 
         ./configure --with-libnetcdf=/home/yourname/location 
       The ck-stuff will be included.

   * For some applications, the GNU Scientific Library (GSL) is needed. 

Recommended Tools to Install libRadtran
=======================================

   We recommend installing the following GNU tools before attempting to
build libRadtran

   * `make' 3.75

     You need the latest version of GNU `make'.  Modifying libRadtran 
     to work with other `make' programs would be  so hard that we
     recommend you port GNU `make' instead.  *Really.* 
     We recommend version GNU `make' version 3.75 or later.

   * GCC 2.7.2.1 and g77 or f2c

     LibRadtran is known to compile and link without problems on
     system with gcc and either g77 or f2c. We recommend GCC version
     2.7.2 or later. 

   In addition Perl version 5.004 or later is needed to run the tests
   and some of the tools.

   The GNU tools are available from http://www.gnu.org and perl from
   http://www.perl.org. 

Reporting Bugs
==============

   There are probably bugs in the Radtran C and Fortran libraries.
There are certainly errors and omissions in the manual.  If you report
them, they will get fixed.  If you don't, no one will ever know about
them and they will remain unfixed for all eternity, if not longer.

   To report a bug, first you must find it.  Hopefully, this will be the
hard part.  Once you've found a bug, make sure it's really a bug. Once
you're sure you've found a bug, try to narrow it down to the smallest
test case that reproduces the problem.   

   The final step when you have a simple test case is to report the bug.
When reporting a bug, send your test case, the results you got, the
results you expected, what you think the problem might be (if you've
thought of anything), your system type, and the version of libRadtran
you are using.  

   Send bug reports to the Internet address
bugs@libradtran.org'.  If you have other problems with
installation or use, please report those as well. 

   If you are not sure how a function should behave, and the manual
doesn't tell you, that's a bug in the manual.  Report that too!  If the
function's behavior disagrees with the manual, then either the libRadtran
or the manual has a bug, so report the disagreement. 

