2.1. Introduction
HGSYSTEM is a PC (personal computer) based package of models which can only be installed as a complete system. In the following installation description it is assumed that the user has a basic knowledge of DOS. As HGSYSTEM works with input files which have to be edited, the user must have a file editor available on his PC and the user must know how to make (simple) changes with this editor. HGSYSTEM does not run under Windows but is called directly from the DOS command line.

2.2. System requirements
HGSYSTEM 3.0 executable code is generated using the Microsoft Fortran Powerstation compiler. This means that the code will only run on a IBM compatible machine with an 80386 or 80486 processor running MS-DOS version 3.3 or later. At least 4 Megabytes of memory is needed. The code will use its own (extended) memory manager (DOSXMSF.EXE, available in the HGSYSTEM directory) while running. The PC should have at least 2.5 Megabyte of free disk space before installation of HGSYSTEM.

Although HGSYSTEM can be run on any machine that meets the above requirements, it is strongly recommended to install HGSYSTEM on a PC with a mathematical co-processor, as calculation times can become quite large if complicated simulations are being done on a machine without a co-processor.

HGSYSTEM 3.0 is delivered on a set of 1.44 MB (high density) 3.5-inch disks, thus an appropriate disk drive is needed for installation.

2.3. Installation
The user can install the executable code and, optionally for expert users, the program Fortran source code.
On the labels of every HGSYSTEM diskette, the correct installation command is given. It is assumed that the diskettes are installed from drive A to drive C, but if other drive names apply, they can be used instead of the default names without any problem. The installation should take place in the correct diskette order (starting with diskette HGSYSTEM-1).

After running the installation program, the PATH command in the AUTOEXEC.BAT file must be extended by adding the following path:
assuming HGSYSTEM is installed on the C drive (change if other drive has been used).

Please check that the FILES parameter in the CONFIG.SYS file is large enough (at least 50).

To use the colours in the interactive HGSYSTEM program, the ANSI.SYS driver should be installed in CONFIG.SYS (consult your DOS manual).

To update your PATH statement, your PC has to be rebooted.

After installation of the executable code, there are three new directories on the hard disk:
  C:\HGSYSTEM     contains all the executable code (programs)
  C:\HGSYSTEM\DATADICT   contains data dictionaries
  C:\HGSYSTEM\STINPUT   contains example (partial) input files

Here it is assumed that HGSYSTEM has been installed on the C drive. Data dictionaries and input files will be discussed in Chapter 3.

It is strongly advised to create a separate working sub-directory (e.g. C:\HGWORK) to run the models. Do not run the models in the three above mentioned directories.

After installing the Fortran source code (optional, only for expert users) a directory named C:\HGSOURCE will have been created. This directory has several sub-directories, one for each model. The source code is installed in a compressed format. The utility program PKUNZIP, which is available in directory C:\HGSYSTEM, can be used to un-compress these files. Giving the command PKUNZIP without any parameters will bring up a information screen on how to use PKUNZIP.