Posted by rbanffy 6 hours ago
I really enjoy CHM's oral histories. I'm slowly working my way thru all of them and there are some real gems in there (Ken Thompson, Dennis Ritchie, Margaret Hamilton, Gordon Moore, Fred Brooks, John Warnock, etc).
My first project there was removing all of the Hollerith from the code. Since Fortran predated strings, you had to manipulate them as integers. When you tied that to the original Fortran dynamic memory system, Dynosour, which used equivalenced arrays as pointers, it was a disaster.
It also gave me an appreciation for JavaBeanFactoryFactory. The original Fortran limited identifiers to six characters, the first of which indicated whether the variable was an integer, logical (bool), or real (float). I will take a 100 character name over ILBNK1 every single time.
GOTOs were surprisingly not a big problem, but structured code is definitely a bit easier to read, especially since it brought the practice of indentation with it.
Overall, it was a great experience but I wouldn't want to do it again, even if the work was interesting.
E3SM [0] is still maintained today, and somewhere around 2mil LoC of F90.
Modern Fortran has a lot of niceties that it brings to the table.
[0] https://e3sm.atlassian.net/wiki/spaces/DOC/overview | https://github.com/E3SM-Project/E3SM
If nothing else, short variable names create an incentive to keep functions small enough you can easily figure out what ILBNK1 means.
The best part is that the code was originally punched onto cards, so most of the early code's comments and documentation were on paper in filing cabinets, if you could find them.
My favorite is SimpleBeanFactoryAwareAspectInstanceFactory
Growing up on early micros, with BASIC, my father had Fortran for the TRS-80.
I took a stab at learning it, but the documentation was reference for calling the compiler, not so much learning the language. And when I found a FORTRAN book, it was quite dated and talking about things like tapes and punches and what not.
So, that effort stalled.
But, my first quarter in college, I took a FORTRAN (77) class. FORTRAN taught on the schools CDC Cyber mainframe.
This was quite a change from 8-bit PET BASIC.
But, most importantly, it was exposure to much of the same concept that an 8-bit computer has, but from a different tact.
This gave me more of a way to view things from a higher level, since I had to make them fit the two different views of how FORTRAN looked at things, how the Cyber presented things, and how BASIC and the PET were "same thing only different".
It also gave me access to a multi-user system, and all of the interesting capabilities it offers.
I remember when they put in their first lab of PCs, and how they started teaching folks Turbo Pascal on micro computers, and I just felt that the users were missing out on a bigger world. "Anyone" can access a PC or micro computer at home, but mainframe or multi user mini access, not so much. It's just a much bigger world out there, and we tend to baby duck what we first see.
Different world today, never had to use FORTRAN professionally, but I am most grateful for the experience of learning it and its environment. Very powerful medium for broader learning.
Also FORTRAN was the only notable computer thing I had "taught" to me (outside of my 20 minute introduction to BASIC by my high school teacher), pretty much everything else I self learned from books and such, even knowing the bulk of it before taking classes in school.
I believe Alan Kay used to say the right perspective is worth 80 IQ points. We should always strive to broaden our experiences and horizons. We get a ton of wrong perspectives, but one perspective you acquired will be a perfect fit for that thing nobody else has the right experiences to figure out immediately.
I worked with a proprietary jet engine analysis software suite written in Fortran 77 and It felt very primitive, albeit fast.
Today I feel like C is a much better choice for speed and readability.
If you really need the fastest performance I dont think Fortran gives that much of an advantage writing assembly.
We found it best to to the front-end and I/O of the code in C and the compute in Fortran. Fastest calculations especially with those tailored libraries.
Modern Fortran has pretty serviceable support for array programming.
My implementation was based on David Rogers' "Procedural Elements for Computer Graphics", one of only two texts available on 3D graphics, the other being Foley and VanDam.
I remember managing my own stack in a language which didn't support recursion. I learned a lot. Good times.
[0] https://medium.com/@kaveh808/8-summer-at-xerox-in-24-bit-col...
It was a very bare-bones language, felt more like a high-level assembly macro language. One thing it did well was expressing formulas with the usual "mathematical" notations (+,-,*,/, parentheses to group operations, variables). I guess this was revolutionary at the time. But the control structures were very limited, everything was basically jumps and gotos. The IF was merely a syntactic sugar for conditional jumps. Of course, functions did not exist in the language.