[ferret_users] MC file: description in the Ferret manual

[Ryo Furue <furue@xxxxxxxxxx>]

Dear Ferret developers,

I found the MC file to be a great feature.  To spread its gospel,
the Scriptures need to be updated, I think.  The Ferret manual

  http://ferret.wrc.noaa.gov/Ferret/Documentation/Users_Guide/current/Chapter10_Converting_to_NetCDF.htm#_VPINDEXENTRY_1090

shows this syntax:

   $FORMAT_RECORD
       D_TYPE               = '  MC',
       D_FORMAT             = '  1A',
       D_SOURCE_CLASS       = 'MODEL OUTPUT',
   $END

which isn't standard Fortran.  A "correct" form looks like


   &FORMAT_RECORD
       D_TYPE               = '  MC',
       D_FORMAT             = '  1A',
       D_SOURCE_CLASS       = 'MODEL OUTPUT',
   /

with at least one blank at the beginning of each line (I think).
Oh, and I think the comment character is "!" not "*" (I haven't
checked).

The namelist wasn't in the Fortran 77 standard, and compiler vendors
implemented their own versions, which resulted in the coexistence
of different syntaxes.  Now, the namelist is in the Fortran 90
standard and later revisions, so that I think virtually all compilers,
including "F77" compilers like g77, accept the standard namelist
syntax.  Nonstandard syntaxes, on the other hand, aren't universally
accepted; For example, the "$FORMAT_RECORD ... $END" syntax is
accepted by g77 but not by the Sun compiler.

Hope this helps,
Ryo