CHAPTER 5

 COMPUTER IMPLEMENTATION



 Since a detailed description of the means of computer implemen-

tation of GENIE would require a detailed description of GENDER, the

description of the computer implementation given here will be restricted

to a discussion of the data structures developed for indexed equations,

a discussion of the memory system developed for the GENDER system, and

a general flow diagram and description of key subroutines.


5.1 Data Structures

 In designing data structures for use in the GENDER system the goal

has been to use as little space as possible while producing a structure

which is compatible with the algorithms which will use it. In order to

do this there has been an attempt to minimize the number of list pro-

cessing type data structures and to use the addressing capabilities of

FORTRAN to minimize searches. In fact, there is only one list of a type

which must be searched in the data structures which contain all of the

index data for the functions and variables.

5.1.1 Index Data Structures

 The first major data structure necessary to the analysis of

indexed equations is the data structure which contains the information

about the function and variable indices. This data structure is the

"INDEX" COMMON area. Two of the vectors in this data structure contain

definitions of the function indices (FIDV) and of the variable indices


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