Graphical Constituent Loading Analysis System

                     GCLAS - Version 2.20 2018/12/03

Instructions for installation and execution are provided below.
After installation, see the gclas.txt file in the doc subdirectory of
the GCLAS installation directory for summary information on GCLAS.

For assistance, enhancement requests, or to report bugs, send e-mail to

                          TABLE OF CONTENTS

                          A. SYSTEM REQUIREMENTS
                          B. DISTRIBUTION FILE
                          C. DOCUMENTATION
                          D. INSTALLING
                              o Installing GCLAS
                              o GCLAS directory structure
                          E. RUNNING THE SOFTWARE
                          F. UNINSTALLING GCLAS
                          G. CONTACTS


A Java Runtime Environment (JRE) is required to install and run
GCLAS. Version 6 or higher is recommended. The latest open-source 
implementation of the JRE for Linux and Microsoft Windows platforms can 
be downloaded from https://adoptopenjdk.net.


The following distribution package (containing the software and
information files) is currently available for Windows systems:


An on-line help manual can be displayed by selecting Help Topics
from the GCLAS Help menu. A user's manual can be is available on the
Web at http://pubs.usgs.gov/tm/2006/tm4C1/.


Installing GCLAS

Prior to installation, it is recommended that you remove (or rename the directory
of) any previously-installed version of GCLAS.

Depending on the operating system and security settings, it may be necessary to 
install GCLAS using administrative rights. This may require that you log in as 
administrator and run the installer or open a command prompt as administrator 
and run the installer via the command line as discussed below.

To install the software, double-click gclas_install_2_20.jar to execute
the installation program and follow the directions on the screen. If the
installation program does not start when double-clicked, open a command 
window in the directory that contains gclas_install_2_20.jar and then type:

java -jar gclas_install_2_20.jar

Follow the installer's instructions to complete the installation.

By default, the software is installed in the directory
C:\Program Files\USGS\gclas2.20.  This is the recommended installation 
directory, but you may use other directories or disk drives.

GCLAS directory structure

The following directory structure will be created (the contents of each
directory are shown to the right):

   gclas2.20                       files NOTICE.TXT and this README.TXT
     `-----bin                      batch file to run GCLAS
     `-----data                     example input data
     `-----doc                      documentation files
     `-----help                     file containing on-line help text
     `-----lib                      class files and software libraries
     `-----lib_data                 constituent library files
     `-----user                     working directory used by GCLAS shortcuts
     `-----Uninstall                uninstaller for GCLAS


Select the GCLAS shortcut from the Start menu to execute GCLAS.  The 
Start menu shortcut is found under Programs, in the Program Folder 
specified during installation (default: USGS).

See the GETTING STARTED text in the upper right-hand panel of the
GCLAS window and the on-line help for assistance with using GCLAS.

Users with multiple installations of JRE should note that the batch
file executed by the GCLAS shortcuts will execute the first java version
found by the operating system.  To execute a different java version,
uncomment and modify as appropriate the lines containing the jrehome
variable in the batch file that executes GCLAS.


To uninstall GCLAS, open a command prompt window (as administrator if
permissions require) and type:

java -jar C:\Program Files\USGS\gclas2.20\Uninstall\uninstall.jar

and follow the prompts. If GCLAS was not installed in the default location,
substitute the correct path to the Uninstall directory.


Inquiries about this software distribution should be directed to:

  U.S.Geological Survey
  Office of Surface Water
  12201 Sunrise Valley Drive  
  Mail Stop 415  
  Reston, VA 20192   

  e-mail:  h2osoft@usgs.gov