Celebrating 70 Years of Fortran (fortran-lang.org)

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.

My favorite is SimpleBeanFactoryAwareAspectInstanceFactory

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.

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 have heard that Fortran is very very good at optimizing array processing due to lack of aliases. That may be one answer today. There’s also value in continuity: in using a language for your task because it can build on what others have built. That applies to any established language, of course… but I could see it reasonably applied if someone wrote some kind of numerical processing library today. They’d write it in Fortran and call it from Python!

However what still makes it a great choice is that it still a relatively simple language compared to C, and maps mathematical formulas to code very well. Inelegant code will still run reasonably fast (which is not the true with C) - so all of these points make it actually a good language when the program is being written by domain experts (i.e., scientists) rather than professional programmers or software engineers.

Its name stands for “Formula Translation,” after all.

> I guess this was revolutionary at the time.

Yes. There was some prior art, but Fortran was the first “mainstream” (for the time) language to offer anything like this.

It is easy to laugh but C programmers have demonstrated that they can't handle variable-sized buffers on the stack, malloc(), free() and all that.

Early versions of FORTRAN [2] didn't even have a stack, like you couldn't write recursive functions, the program would take parameters for array sizes when it boots and the memory layout would all be figured out at the beginning. When I was developing a display controller for persistence of vision displays for the AVR-8 it drove me nuts how the C compiler kept moving the stack pointer around all the time for no real reason when an assembly program could move data to and from statically allocated structures. [3]

FORTRAN and COBOL came out around the time Syntactic Structures did so of course there was not an established theory for how to parse grammars, no parser generators, etc. No Dragon Book, but the heroic techniques used to develop compilers in that age are legendary if not quite lost.

I wrote some FORTRAN programs in high school on a VAX, in a comparative programming languages class in college, converted a lot of FORTRAN algorithms into statically allocated Java in grad school in 1990 and in my postdoc I wrote a generator that wrote JNI bindings for LAPACK.

[1] ... e.g. the typical struct is < 4096 bytes

[2] before the FORTRAN 90 standard though you could set the /RECURSIVE flag on DEC FORTRAN

[3] we were done such a disservice by all those "it's so elegant to compute Fibonacci in a better programming language than BASIC" articles in Creative Computing because recursion is one of those things, like C's memory management, that most programmers can't really handle.

It beats LISP by a year and COBOL by two years.

Apparently not. Fortran 90 standard was published 35 years ago, in 1991. But a majority of comments in this thread are about FORTRAN 77. It's like the last 35 years didn't happen at all.

I used modern Fortran in undergrad and grad research from 2011 to about 2015. I rarely ever encountered FORTRAN 77 back then, and never had to write any. I worked as an intern at NIST and LANL during that time too and it was modern Fortran there as well. At NIST, as far as I'm aware, that group had been using modern Fortran for probably a decade or more before I started in 2011.

I didn't have to write any FORTRAN 77 until 2025 in my current job when I was given a legacy code to work with.

When I first started, with BASIC, my variable of choice was T simply because it was easy to type NEXT T in the FOR loops (why not R? I dunno...T just stuck).

FWIW, I started programming in 1965, in FORTRAN II.

“I used to be a mathematics professor. At that time I found there were a certain number of students who could not learn mathematics. I then was charged with the job of making it easy for businessmen to use our computers. I found it was not a question of whether they could learn mathematics or not, but whether they would. […] They said, 'Throw those symbols out—I do not know what they mean, I have not time to learn symbols.' I suggest a reply to those who would like data processing people to use mathematical symbols that they make the first attempt to teach those symbols to vice-presidents or a colonel or admiral. I assure you that I tried it.” — Grace Hopper