Program mark3_to_gvh converts a database in MARK-III DBH or a pair 
of database files at two frequencies of the same experiment to
GVF format.

I. Assumptions:
---------------

1) The MARK-III database files are imported to Calc/Solve 
   database system using program catlg.

2) The MARK-III database files are already processed at 
   least by Calc (version 2), but preferably with DBCAL,
   i.e. inserted calibration information (version 3), or
   with Solve, i.e. intermediate results of data analysis
   are inserted (version 4 or higher).

3) Post-Solve configuration file $SAVE_DIR/vcat.conf 
   exists and defines all the fields.

Practically, after you downloaded the latest version of 
database file(s) in MARK-III DBH, you insert them into
the database system using program catlg. Then you 
can convert database files to GVH format. After that 
original files in MARK-III DBH and corresponding records
in the catalogue system are not used and can be discarded.

II. Usage:
----------

mark3_to_gvf {database_x} {database_s} {gvh_db_name} {gvh_env_name} {a|b}

1st argument -- the database name of for the upper band (X-band). 
                Leading $ in the database name can be omitted.

2nd argument -- the database name of for the lower band (S-band).
                Leading $ in the database name can be omitted.
                If the experiment had only one band, or the database 
                file for the lower band is lost, the second argument 
                should be No_Sband.

3rd argument -- experiment name in GVF format. Although any combination
                of letters and digits in a 16-characters long name
                is allowed, it is strongly recommended to follow the 
                the following naming convention:
                yyyymmdd_eeeeeee

                where yyyy is the year, mm is the month in a range of
                01 to 12, dd is a day of month in a range of 01 to 31
                and eeeeeee is experiment name from 1 to 7 characters
                in low case. For IVS observations this should be IVS
                experiment ID.

4th argument -- 10-characters long database name. The following convention
                is strongly recommended:

                yyyymmdd_s

                where yyyy is the year, mm is the month in a range of
                01 to 12, dd is a day of month in a range of 01 to 31
                and s is a one-character long lower case suffix. 
                Suffixes from a to e are reserved to IVS experiments.
                Suffixes x, y z is reserved for tests. Suffixes from f
                to w can be used for non-IVS experiments.

5th argument -- Format of the output database: b for binary, a for ascii
                ab for both binary and ascii. Post-Solve expects to find
                the data in binary format.


III. Examples:
--------------

mark3_to_gvh_exe  81JAN13XA  No_Sband   19810113_onstie       19810113_a  b
mark3_to_gvh_exe  95MAR13XN  95MAR13SN  19950313_rdmsw1       19950313_d  b

