Defines a list of variables or array names and associates that list
  with a unique group-name, which is used in the namelist I/O
  statement.

     NAMELIST /group/nlist[[,]/group/nlist]...

     group  Is the name of the group.

     nlist  Is the list of (no more than 250) variable
            names, separated by commas, that are to be
            associated with the preceding group.

  Dummy arguments can appear in a namelist.

  The following variables cannot appear in a namelist group:

   o  An array dummy argument with nonconstant bounds

   o  A variable with assumed character length

   o  An allocatable array

   o  An automatic object

   o  A Fortran 95/90 pointer

   o  A variable of a type that has a pointer as an ultimate
      component

   o  A subobject of any of the above objects

  You can use namelist I/O to assign values to elements of arrays or
  substrings of character variables that appear in namelists.

  The namelist entities can have any data type and can be explicitly
  or implicitly typed.

  Only the entities specified in the namelist can be read or written
  in namelist I/O.  It is not necessary for the input records in a
  namelist input statement to define every entity in the associated
  namelist.

  The order of entities in the namelist controls the order in which
  the values are written in the namelist output.  Input of namelist
  values can be in any order.

  A variable can appear in several namelists.