Running the numerical model VS2DRTI outside of the
graphical user interface.


Contents
--------
A. Introduction
B. Input data requirement for VS2DRT
C. Making the executables easily assessable
D. Running VS2DRT

A. Introduction
---------------

It is anticipated that most users will not need to run
the numerical model VS2DRT outside of the graphical user
interface. If you need to make manual changes in the
model input file (VS2DRT.DAT), you can 
export this file from the preprocessor,
make the changes in a text editor, and then run the simulation
in the postprocessor in standalone mode.  Alternatively,
you can run VS2DRT in batch mode outside of the GUI;
this approach can greatly reduce execution times.

The VS2DRTI software package includes executables for
running VS2DRT without the user interface. Information on how to run 
these programs is given below.


B. Input data requirement for VS2DRT
-----------------------------------

The numerical model VS2DRT requires the following two input files:

vs2drt.fil -  This is known as the "namelist file" and contains the names 
             of input file and output files to be opened by the program. 
             This file must be named vs2dt.fil. The first line of this 
             file must contain the name of the model data file, which is 
             described next.

vs2drt.dat - This is known as the "model data file" and contains input 
             data to VS2DT. The default file name is vs2drt.dat. However, 
             this file can have a different name as long as it matches 
             the name on the first line of the namelist file.

These two files can be easily generated by the VS2DRTI preprocessor
by using the "Export data" command from the "File" menu. Alternatively,
the model data file vs2drt.dat can be created manually by following the
instructions in the file vs2drt_Input_Instructions.pdf.

If solute transport is simulated, two additional files are required:

input.pqi   - This file contains geochemical information, such as initial 
              and boundary concentrations and definitions of mineral equilibria, 
              ion-exchange, surface-complexation, gas, solid-solution, and 
              kinetic reactants. This input file can be created by the user 
              by using the PhreegcI software (Charlton and Parkhurst, 2002).  
phreegc.dat - This the Phreeqc database file that is included in the
              download package.

The above files should be kept in a single directory. When the 
program is executed, output files containing simulation results will be 
generated in the same directory.



C. Making the executables easily assessable
-------------------------------------------

The executable for running VS2DRT is vs2drt.exe; it
is located in the "bin" directory under the software 
installation directory. To make the executable accessible from 
any directory, without needing to type the full pathname, the bin 
directory must be included in the PATH environment variable.

On Windows 7, XP, and 2000 systems, click the "Start" button, 
select "Settings", and then "Control Panel". Double-click "System"
and select the "Advanced" tab, and click the "Environmental Variables"
button.

If a "PATH" environmental variable already exists, then click on it so 
that it is selected. Next, click the "Edit" button. In the "Variable Value" 
box, append the following to the end

  ;<installation_directory>\bin

where <installation_directory> is the directory in which the software
is installed. (Don't forget the leading semicolon.) For example, 
if the software is installed in the default location, you would append 

  ;C:\Program Files\USGS\vs2drti-1.6.0\bin
  
Click "OK". 

If a "PATH" environmental variable does not exist, then click the "New"
button. Enter "PATH" in the "Variable name" box. In the "Variable value" 
box, enter

  <installation_directory>\bin

where <installation_directory> is the directory in which the software is 
installed. For example, if the software is installed in the default 
location, you would enter

  C:\Program Files\USGS\vs2drti-1.6.0\bin

Click "OK".


On Windows 98 systems, add the following line to the end
of AUTOEXEC.BAT:

  PATH=%PATH%;<installation_directory>\bin

where <installation_directory> is the directory in which the software
is installed. For example, if the software is installed to the default
location, the above line would be

  PATH=%PATH%;C:\Program Files\USGS\vs2drti-1.6.0\bin

Reboot your system after modifying AUTOEXEC.BAT.




D. Running VS2DRT
----------------

To run the VS2DRT:
1. Open a DOS command prompt window.
2. Change to the directory containing the input files (see Section B).
3. If you have added the "bin" directory to your PATH environmental
   variable (see Section D), type the command "vs2drt" (without quotes).
   If you chose not to add the "bin" directory to your PATH environmental
   variable, you will have to type the complete pathname. For example,
   if you installed the software to the default location, you would type
   the command "C:\Program Files\USGS\vs2drti-1.6.0\bin\vs2drt" (including quotes).