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Fortran 2000 Committee Draft
The formal position is that a CD (Committee Draft) Registration and Approval Ballot is in progress. The deadline for comments (from national bodies) is 27 December. Each national body will have its own deadline ahead of 27 December, so be sure to submit your personal comments to your national body well before then. For the USA, they should be sent to Deborah Donovan, email: ddonovan@itic.org. For the UK, they should be sent to David Muxworthy, email: d.muxworthy@ed.ac.uk.
John Reid, ISO/IEC JTC1/SC22/WG5 Convener
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ISO/IEC JTC1/SC22/WG5 N1494
Committee Draft revision of ISO/IEC 1539-1:1997 - Programming Language Fortran - Part 1: Base language
Abstract
Fortran is a computer language for scientific and technical programming that is tailored for efficient run-time execution on a wide variety of processors. It was first standardized in 1966 and the standard has since been revised three times (1978, 1991, 1997). The revision of 1991 was major and those of 1978 and 1997 were relatively minor. This proposed fourth revision is major and has been made following a meeting of ISO/IEC JTC1/SC22/WG5 in 1997 that considered all the requirements of users, as expressed through their national bodies.
The significant enhancements in the 1991 revision were dynamic storage, structures, derived types, pointers, type parameterization, modules, and array language. The main thrust of the 1997 revision was in connection with alignment with HPF (High Performance Fortran).
The major enhancements for this revision are
(1) Derived type enhancements: parameterized derived types, improved control of accessibility, improved structure constructors, and finalizers.
(2) Object oriented programming support: type extension and inheritance, polymorphism, dynamic type allocation, and type-bound procedures.
(3) Data manipulation enhancements: allocatable components, deferred type parameters, VOLATILE attribute, explicit type specification in array constructors, pointer enhancements, extended initialization expressions, and enhanced intrinsic procedures.
(4) Input/output enhancements: asynchronous transfer, stream access, user specified transfer operations for derived types, user specified control of rounding during format conversions, named constants for preconnected units, the flush statement, regularization of keywords, and access to error messages.
(5) Procedure pointers.
(6) Support for IEC 60559 (IEEE 754) exceptions.
(7) Interoperability with the C programming language.
(8) Support for international usage: access to ISO 10646 4-byte characters and choice of decimal or comma in numeric formatted input/output.
(9) Enhanced integration with the host operating system: access to command line arguments, environment variables, and processor error messages.
In addition, there are numerous minor enhancements.
Except in extremely minor ways, this revision is upwards compatible with the current standard, that is, a program that conforms to the present standard will conform to the revised standard.
The enhancements are in response to demands from users and will keep Fortran appropriate for the needs of present-day programmers without losing the vast investment in existing programs.
For those of us under 50, here's some history of the granddaddy of all high-level programming languages.
IIRC, my former graduate advisor and professor was on the team that wrote a very early Fortran compilers at MIT in the late 50s, written entirely on punch cards. We've come a long way in ~50 years.
:wq
The list goes on and on, but these are changes that where implemented in Fortran90. Since then, attepts have been made to turn Fortran into an OO language. Aid i18n and other things to make Fortran less of a CS language.
The reason you might want to try out Fortran is because of speed. Under gcc/Linux C may be the fastest language, but under Solaris, Irix, AIX and other oldschool OSes, Fortran is still speed king, for two reasons.
Firstly, the Fortran compilers are well tuned mature products under these platforms.
Secondly, the Fortran language makes all kinds of assumptions that the programmer must adhere to. Example: If a function recives two arrays, they must not overlap. This allows Fortran compilers to do loop unrolling in cases where a C-compiler cannot.
Try out fish, the friendly interactive shell.
Fortran is still used quite a bit in scientific and engineering circles. There is a HUGE code base that people (understandably) do not want to give up. I spent three years in the mid-90's developing groundwater numerical models with Fortran90.
Some reasearch instutituions and software development companies have starting using C; however, mainly for pre- and post-processors. Many are still using Fortran numerical engines.
Another reason that Fortran was still popular (at least through the 90's) was that some of the major compilers (Such as IBMs Fortran complier) ROCKED. Some simulations that I was working on took weeks to peform and the compliers were very good at optimizing the Fortran code -- without the scientist getting too close to the hardware.
I must admit; however, that today all my programming is either done in C, Objective-C, or Perl -- even though gcc will compile Fortran code. (Can you believe I wrote a postscript driver for printing evelopes on our lab's printer in Fortran! )
I think in general it helps to teach more than one language. The current trend is to have a "core language" that schools teach in excruciating detail so that students will be able to go out and get a job right away, because they have a "skill".
But much of the time, they don't understand how or why what they've been taught actually works, which makes learning other programming languages vastly more difficult, since they're focusing on what's different in the syntax rather than on what's the same in the semantics.
... is what FORTRAN is good for: number crunching. F77 is a perfect tool for many scientists who don't care about pointers or object oriented programming or nice graphical output subroutines or any other nice things that other programming languages have. They want something that will do some number crunching for them and won't screw up or cause problems.
FORTRAN is simple. It works like many mathematicians and scientists think it should. It meshes well with what they really want to do in a good number of cases. The level of abstraction is perfect for many of them.
FORTRAN will take a long time to die because of this. Personally, I like more real-time interpretive languages like IDL. But when it comes down to something that is pure number crunching that'll take a few hours, I'll gladly have FORTRAN. That's why so much in the sciences is written in FORTRAN, then the data is output and run through other programs to do the pretty plotting and further interpretation.
FORTRAN just works, has worked for 30+ years, and with the amount of incredibly useful code still around, will still work for decades to come. Granted, I don't necessarily like some of the proposed changes, but as long as everything works like it did before with F77 code, I think no one will (or should) mind.
-Jellisky