Oregon District
MODIFICATIONS OF THE U.S. GEOLOGICAL SURVEY MODULAR, FINITE-DIFFERENCE, GROUND-WATER
FLOW MODEL TO READ AND WRITE GEOGRAPHIC INFORMATION SYSTEM FILES
Contact Person: Leonard L. Orzol 503-251-3270 llorzol@usgs.gov
Originally, the user entered ARC/INFO software and then operated MODFLOWARC by using the MODFLOWARC.aml. MODFLOWARC.aml needed one argument, a name of an ASCII file, which contain the FORTRAN unit numbers for each package activated in MODFLOW and the associated filename where the data was stored or written to. In version 5.0 of MODFLOWARC, C functions are used to transfer data out of or into INFO datafiles and the ground-water flow model MODFLOW. The user no longer needs to enter ARC/INFO software.
The original version of MODFLOWARC was developed using FORTRAN subroutines available within the version 4.3 of ARC/INFO software to read and write INFO datafiles. In later version of ARC/INFO software, ESRI incorporated these FORTRAN subroutines into ARCSDL (ARC Software Development Libraries). In version 5.0 of MODFLOWARC, the FORTRAN subroutines were replaced by C functions. These C functions were developed by Randy Deardorff [rdeardor@r0serv.r10.epa.gov] and are distributed as public domain software.
In the manual of MODFLOW, Techniques of Water-Resources Investigations of the United Sates Geological Survey Book 6 Chaper A1, a sample problem is presented. This sample problem is used to demostrate how to operate MODFLOWARC. All the necessary files are include in ASCII format and in binary format for INFO files. A script or shell file is also include which activates MODFLOWARC and initializes the proper links between the FORTRAN unit numbers and the data for each package in MODFLOW. The user must first change the paths to the Info files containing the input data arrays. These instructions are summarized in the published paper called awra.ps. This file is found in the ../docs directory and should printed before working with the sample problem.
A script or shell file consist of commands to connect the FORTRAN unit numbers with the proper files containing the package arrays and operate MODFLOWARC. The symbolic command is used in the script file to connect FORTRAN unit numbers and data arrays. For an example the following file is from the sample problem and illustrates the contents of a script file:
# Script to run modflowarc
#
# 07April1995 LLOrzol
#
rm modflow.list
ln -s bcf.arc fort.11
ln -s wel.arc fort.12
ln -s drn.arc fort.13
ln -s rch.arc fort.18
ln -s sip.arc fort.19
ln -s out.arc fort.20
modflowarc modflow.list
mv fort.76 hedbud
mv fort.77 ddnbud
rm fort.??
[ Back to MODFLOWARC Page]
Last modified: Fri Feb 16 09:14:18 1996