When I started using SPSS in 1972, there was documentation on how to use FORTRAN to contribute. This allowed one to use all the data definition etc without reinventing it. There wee a skillion subroutines one could call.
One had to be careful when using DEC FORTRAN which had many features that were not available on other platforms. For example, DEC FORTRAN always cleared memory before assigning it to an individual user. On some other platforms it was imperative to initialize memory. I do not recall if it was early, but by 1977, DEC FORTRAN had a
PARAMETER statement, for example in adapting INDSCAL on the DEC ten to handle by 210 10x10 similarity matrices for my dissertation I could change DIMENSION statements something like this in a file
Parameter NSTIM =10
Parameter NSUBJ =210
The main code would have
some statement to include the small file and then
Dimension NDATA (NSUBJ, NSTIM, NSTIM)
One also had to avoid using some kinds of DIMENSION statements like
Dimension IPCT (-100, 100)
Dimension IYEAR (1776, 1980)
One also could not rely on automatic checking for a subscript being out of bounds for example
if a value of IYEAR were 1770 when the array was
Dimension IYEAR (1776, 1980)
Art Kendall
Social Research Consultants