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Compaq Fortran for Linux Alpha Released
Compaq Fortran for Linux Alpha systems is a full-language Fortran 95 implementation. Fortran programs using the latest features as well as traditional Fortran 77 programs will be able to take advantage of the highly optimized Alpha code generation technology to take advantage of the Alpha processor's leadership performance. The compiler also supports most of the popular language extensions available on other Compaq platforms (OpenMP and HPF features are not currently supported.)
Accompanying the compiler and optimized run-time libraries is Ladebug, a robust and easy to use debugger that will simplify the debugging of all of your Fortran applications.
Also provided is the Compaq Extended Math Library (CXML), a library of technical and scientific subroutines.
Compaq Fortran for Linux Alpha Systems is available as a free download under a Technology Enthusiast license for non-commerical use. A Commercial Use license and media kit is available for US$399 - attractive multiple-license pricing is also available.
For more information, please visit the Compaq Fortran web site.
When one says that Fortran is faster than C/C++ one means that if you have two versions of the same program, one written in Fortran and the other in C/C++ then the fastest executable will be likely the compiled Fortran version.
:-)
The reason for this is usually due to the control over aliasing that Fortran has. This allows better compiler optimizations that result in faster executable. Moreover Fortran 95 has lots of constructs that give hints to the compiler on possible optimization: the array sintax (so the compiler knows that order doesn't matter), the intent of paramters (in, out, inout), pure functions (functions with no side effects), allocatable arrays (that guaratee no aliasing) are some exemples.
Oh, and yes, it is very nice to borrow some APL features
Paulo.
PS: I am not really a Fortran fan, I am fan of using the best language to solve a given problem. In the case of numerical problems, Fortran seems the best. I would gladly program in C/C++ if I could prove to my advisor that I can get a faster executable by doing so.
Our Intel Windows compiler (Compaq Visual Fortran) is very popular, and we do get frequent requests for an Intel Linux version. There are no current plans to do that, but then again, a year ago there were no plans to do Linux at all. So, "never say never"...
If you feel that we should do an Intel compiler, and would be willing to pay for it, let us know. (Feel free to send me mail with your comments.)
Steve Lionel
Free-but-not-free license is disappointing, but what else can you expect from a company like Compaq.
IIRC, this has actually been available for quite a while in beta form. This is, however, good news - the Digital (I can't bear to call it Compaq) Alpha compiler for Fortran produces code that is anywhere up to 2-3 times as fast as g77 (currently, that is. I'm sure g77 will get better). Anybody doing scientific work on an Alpha under Linux (and, let's face it, most people that have Alphas use them specifically because they're good at scientific work) can benefit from this.
(FWIW, I've used the Digital C compiler for Linux, and it produces excellent code - better, in most cases, than gcc.)
OTOH, I find it hard to imagine that too many ppl on Linux/Alpha have a big use for fortran anyhow..
You have got to be kidding. An awful lot of scientific applications are written in Fortran for two reasons:
1: Many scientists started using Fortran a long time ago, and they can't be bothered switching now (not to mention all that legacy software they've stocked up).
2: The floating-point math libraries for Fortran on the Alpha are way faster than just about any other language on any desktop platform, period.
If Fortran wasn't available for Alpha, the architecture would have most likely sunk into obscurity a long time ago.
Freshman year, my advising seminar involved developing a method for modeling sail boats. We were given a spec file and implemented some algorithms to scale the boat, apply wind, etc. We wrote some code, and used some code that the professor developed years earlier. The language in use? Fortran-77. Developing that on our Sun Workstations was a travesty.
Fortran is STILL heavily used in academic circles because the code already exists. My friend, when interviewing for an on campus job doing mathematical modeling, was asked if he knew Fortran. He convinced the guy to let him do it in C++, but some professors would insist on Fortran.
From my experience, for doing scientific analysis, Fortran is fine. Fortran, C, PASCAL, BASIC, it really doesn't matter, the structured languages are all almost identical with slightly different syntax.
While object oriented techniques make sense for real software development, if you merely want to run a particular algorithm on a lot of data points, any structured language will do.
Older researchers learned Fortran and probably never moved to the newer languages. Fortran is really clean, and if your existing code is in Fortran, why migrate to a newer language. While I haven't read the newer Fortran specs, I believe they implement much of the functionality of other structured languages (although I'm assuming no real memory control).
Fortran makes it VERY easy to develop robust applications for number crunching without any risk of memory leaks, etc. Additionally, groups may already have thousands of lines of code already written and just need to write a bunch of 15-20 line applications utilizing them to do different forms of analysis.
Fortran on the Alpha under Linux may be the "killer app" to move Linux into acadamia. I don't mean in the school's IT departments, but into research departments. For departments that need to process a LOT of data points, allowing students to develop code at home or on public workstations and then run the massive calculations on their Alpha machines may be a real cost and time saver.
If Compaq gets the rest of their compilers in line, then Linux/Alpha may become huge.
Your statement that:
I find it hard to imagine that too many ppl on Linux/Alpha have a big use for fortran anyhow..
is kinda silly. Outside of home users, people don't buy a system and then find a use. People have a need and pick the best platform.
If you have a lot of existing Fortran code and want to utilize it for new processes and do massive calculations, you pick the best platform available. If current computing capabilities fit your need, you use them. If you need a newer machine to process all the data, you buy a new machine. If the Alpha platform under Linux is the best platform and you have a lot of Fortran to process, I can bet that you'll be buying a new Alpha machine running Linux.
Alex
At least that what the notice quoted at Linux Today says.
--
It's October 6th. Where's W2K? Over the horizon again, eh?
Sheesh, evil *and* a jerk. -- Jade
Are the Open Source zealouts at it again?
Fortran itself has quite a limited number of serious users
Ummm...no. A huge number of serious scientific and engineering simulations are coded in Fortran. It is a fairly low-level language that has unmatched capabilities for optimization and parallelization.
For God's sake, take a look at O'Reilly's High Performance Computing"
And don't whine about the license.
1. Compiler optimiztions are very much tied to the architecture, so it's not surprising that the best compiler writers for a high-end RISC platform are indeed employed by same company. In this case, it's "a company like Compaq". The old Digital would have been no different.
2. If a 10% increase in hardware speed costs $10,000, then $400 for a compiler is nothing, even if the executable is only 10% faster than that of g77. And Lo and Behold, it runs on Linux, not the costly, closed-source Tru64 UNIX!
Christ, what a bargain!
-- Liquor up front, poker in the rear.
Unfortunately it seems that most slashdot readers don't know much about the new Fortran standard (Fortran 95) and keep on saying that Fortran is an old language, etc. I will try to point out some things:
1) Fortran 95 is structured.
2) Fortran 95 has abstract data types (called modules). But certainly it is not OO (lacks inheritance). Oh, it has overloading too.
3) Fortran 95 has cool matrixes that are, in a certain sense, close to Matlab matrixes. For exemple the code
A(:,3) = 1 + 2*A(:,4)
changes the second column of the matrix A to 1 plus two times the forth column. Of course this serves as a good hint to the compiler that the implicit loop above can be done in parallel.
4) Fotran 95 was designed with efficiency in mind. A good exemple is the distiction between allocatable arrays and regular pointers, so that you can have dynamic allocation with a better control of aliasing.
6) Fortran 95 is usually faster than C/C++. There is some effort to change this (see Blitz++ library or the MTL, for information http://www.oonumerics.org).
7) The main disadvantage of Fortran 95 for a scientific linux user is the lack of free (as in freedom compilers). g77 only implements FORTRAN 77 (plus some extensions), it is not a Fortran 95 compiler.
Hope that helps.
Paulo.