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PROGRAMMER’S MANUAL
alternative computations, printing additional results, writing data in alternative formats or other advanced features that may be performed.
As an introduction to the ASTROS system, Chapter 2 contains a description of the software structure of
ASTROS, both to provide a resource for the system administrator and to be a road map for the application user in identifying specific modules relevant to the task of interest. Chapter 2 attempts to introduce
the user to the totality of ASTROS source code and their interrelationships so that subsequent reading
will be more readily interpretable: in essence, Chapter 2 provides a nomenclature section enabling the
reader to identify (with the inevitable exceptions) the major unit (module) or functional library to which a
particular program belongs. This shapter provides a framework for subsequent shapters in the Programmer’s Manual.
Chapter 3 is devoted to the installation of the ASTROS system on various host computers. The steps
involved in installing the system are given, followed by detailed documentation of all the machine and
installation dependent code. Sufficient detail is given to allow someone familiar with the target host
system to write a set of machine-dependent code for that machine or site. This documentation is followed
by the description of the System Generation Process (SYSGEN) and its inputs. These inputs, along with
the SYSGEN program, define the system database which, in turn, defines system data to the ASTROS
executive. It is these inputs which the researcher may wish to modify to define a new module, define a
new set of inputs or make other advanced modifications of the system. A brief presentation of the order of
the operations that follow preparation of the machine dependent library is given to complete an installation of the system.
Chapters 4 through 8 contain the formal documentation of the ASTROS modules. Chapter 4 documents
those portions of the code that are considered to be at the system level. This means that the user need not
be aware of their existence but they are important in the overall system architecture. Further, they
perform many tasks of which the user may want to be aware if any system modifications are to be made.
Chapters 6 through 8 document the utilities that are associated with the ASTROS application modules,
matrix operations and the database. These shapters are the most important from the view of the advanced researcher/user in that these are the software tools from which additional capabilities can be put
together with reasonable rapidity. In each case, the executive (MAPOL) and application interface is fully
defined and the algorithm of the utility is outlined.
Chapter 9 contains the documentation of the data structures on the CADDB database that are used by
the ASTROS system. The contents and structure of each database entity are given along with an
indication of the module that generates the data and which modules use the data. For matrix entities,
the relevant shapter of the Theoretical Manual is also referenced since the entity contents are more
clearly understood in the content of the equations that are highlighted there.
Chapter 10 contains a presentation of notes for the ASTROS application programmer. It is felt that the
ASTROS system has been designed with sufficient flexibility that the additional features or minor
enhancements are desired. Chapter 10, therefore, attempts to address some issues involved in writing an
ASTROS module. Rules and guidelines are given which will help the programmer avoid complications
arising from the interface of the new module and application utilities are also given. Particular emphasis
is placed on the memory management utilities and the database utilities since these require a more
sophisticated interface than the simple application utilities.
1-2 INTRODUCTION
ASTROS