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added continue directive information

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rak
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Ricky Kendall 1996-10-21 19:13:13 +00:00
parent 3fb8bbb78c
commit e6d26b3c32
2 changed files with 53 additions and 30 deletions
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30
doc/user/mp2.tex
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@ -4,12 +4,12 @@ The RI-MP2 module can be invoked by specifying
\begin{verbatim}
TASK RI-MP2
\end{verbatim}
on a \verb+RESTART+ job -- the MO vectors and database from the SCF
calculation must be present. At present, the RI-MP2 does not have its
own input module, instead it can be controlled by \verb+SET+ing
entries in the database. Currently recognized entries are described
below. {\em The names of these entries in the database will change in
the very near future.}
on a \verb+RESTART+ or \verb+CONTINUE+ job -- the MO vectors and
database from the SCF calculation must be present. At present, the
RI-MP2 does not have its own input module, instead it can be
controlled by \verb+SET+ing entries in the database. Currently
recognized entries are described below. {\em The names of these
entries in the database will change in the very near future.}
Alternatively, the fully-direct MP2 module using conventional
four-index transformation (see also section \ref{sec:fourindex}) may be
@ -19,15 +19,15 @@ invoked by the input line
\end{verbatim}
In future releases, the two MP2 modules will be amalgamated into a
single task where the choice of method will be an input parameter. In
cases where the MP2 is restarted using a \verb+RESTART+ directive --
the MO vectors and database from the SCF calculation must be present.
Currently, there is no specific MP2 input module, instead the
behavior can be modified by using the \verb+SET+ command on the
database entries. Currently recognized entries are described below,
the first three entries apply to both the \verb+RI-MP2+ and
\verb+DIRECT_MP2+ tasks while the remainder are specific to
\verb+RI-MP2+. {\em The names of these entries in the database are
subject to change in the near future.}
cases where the MP2 is restarted using a \verb+RESTART+ or
\verb+CONTINUE+ directive -- the MO vectors and database from the SCF
calculation must be present. Currently, there is no specific MP2
input module, instead the behavior can be modified by using the
\verb+SET+ command on the database entries. Currently recognized
entries are described below, the first three entries apply to both the
\verb+RI-MP2+ and \verb+DIRECT_MP2+ tasks while the remainder are
specific to \verb+RI-MP2+. {\em The names of these entries in the
database are subject to change in the near future.}
\subsection{Frozen Orbitals}

53
doc/user/top-level.tex
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@ -1,34 +1,57 @@
\subsection{START and RESTART}
\subsection{START, CONTINUE and RESTART}
\label{sec:start}
This is a startup directive (section \ref{sec:inputstructure}).
A \verb+START+ or \verb+RESTART+ directive is optional but care must
A \verb+START+, \verb+CONTINUE+ or \verb+RESTART+ directive is optional but care must
be taken if no directive is presented since the behaviour of the code
will vary depending upon the existence of the database.
\begin{verbatim}
(RESTART || START) [<string file_prefix>] [rtdb <string rtdb_file_name>]
(RESTART || CONTINUE || START) [<string file_prefix>] [rtdb <string rtdb_file_name>]
\end{verbatim}
\verb+START+ indicates a startup calculation in which the database is
created and any existing database is destroyed. \verb+RESTART+
indicates that an existing database should be used and an error will
result if it does not exist. All files created by NWChem are by
default prefixed with the string specified on the directive, which
defaults to the basename of the input file (i.e., the input file name
with the directory and any trailing \verb+.*+ stripped off). Note
that if you change the file prefix in a restart job, NWChem will be
unable to locate most files automatically. The \verb+RTDB+ keyword
permits specification of the name of the database which otherwise
defaults to \verb+<file_prefix>.db+ in the directory for permanent
files.
created and any existing database is destroyed. \verb+RESTART+ or
\verb+CONTINUE+ indicate that an existing database should be used and
an error will result if it does not exist. All files created by
NWChem are by default prefixed with the string specified on the
directive, which defaults to the basename of the input file (i.e., the
input file name with the directory and any trailing \verb+.*+ stripped
off). Note that if you change the file prefix in a restart job,
NWChem will be unable to locate most files automatically. The
\verb+RTDB+ keyword permits specification of the name of the database
which otherwise defaults to \verb+<file_prefix>.db+ in the directory
for permanent files.
If no \verb+START+ or \verb+RESTART+ directive is presented then
The difference between \verb+CONTINUE+ and \verb+RESTART+ is subtle
but useful. \verb+CONTINUE+ will not parse any new input data before
it does the task stored in the database file. \verb+RESTART+ will
parse new input data and overwrite any existing data if appropriate.
\verb+CONTINUE+ should be viewed as {\it restart and finish} the
old task and also do any new tasks that are input. \verb+RESTART+
should be viewed as restart with information available, new input is
also parsed, and do the tasks outlined in the input so the old task
may be discarded. \verb+CONTINUE+ implies restart the old task and
\verb+RESTART+ implies restart with possibly a new task.
For example, in a SCF energy calculation where you underestimated the
time necessary and the job was killed by the scheduling software. You
could use either \verb+CONTINUE+ or \verb+RESTART+ directive with the
appropriate file prefix and database specifiction to complete the
task. On the other hand if you wanted to finish the task and do an
additional SCF energy computation with a new geometry you could use
\verb+CONTINUE+ directive, input the new geometry and use a single
task directive for the second energy point. Again, the difference is
subtle but useful.
If no \verb+START+ \verb+CONTINUE+ or \verb+RESTART+ directive is
presented then
\begin{itemize}
\item the default file prefix is used,
\item the default database name is used,
\item if the default database exists, then the job is assumed to be
a restart, otherwise it is assumed to be a startup.
\item continue is never assumed.
\end{itemize}
E.g., if running NWChem with the command \verb+nwchem water.nw+ and no