TweetFollow Us on Twitter

LS FORTRAN 3.0, Pt 2
Volume Number:8
Issue Number:2
Column Tag:Jörg's Folder

Language Systems FORTRAN 3.0

By Jörg Langowski, MacTutor Regular Contributing Author

[Due to a bug that showed itself in Quark XPress 3.1, portions of this article were not printed properly in the April/May issue. The relevant portions are reprinted here. Just goes to show, to err is human, but to really foul things up takes a computer. - Ed.]

Language Systems FORTRAN 3.0

FORTRAN 2.1 was already very robust, generated good, fast code, and all in all, allowed programs that ran on mainframes to be ported very quickly to the Macintosh. Also, subroutines could be assigned to menu items, and the runtime system would handle the menu selections automatically for you, files could be OPENed using the standard file dialogs, and many more goodies.

A Multi-dialect FORTRAN

When I opened the 3.0b2 version of the LS FORTRAN (LSF) compiler, amazingly enough I discovered that one could still make substantial improvements to this development system. First of all, Language Systems proved that one can actually make several existing FORTRAN dialects live happily together in one system. Although I have only VAX programs to test here, I believe their claim that Cray, Microsoft, Data General, and of course standard ANSI 77 FORTRAN programs mostly compile without modifications and produce the expected results. There is a whole section of the manual (20 pages, to be precise) devoted to describing the compatibility with other systems, and the changes that may still be necessary for porting the programs. The manual - or rather Karen Rall, who wrote it - “thinks for you”; the Mac user who has never before transferred a FORTRAN program from a mainframe will even get instructions about file-transfer protocols, Macintosh file attributes and VAX record types. There are -vax and -cray compiler switches for porting programs from those respective machines. Even the VAX pre-connected filenames SYS$INPUT, SYS$OUTPUT, SYS$PRINT and SYS$ERROR are supported. Also, all Microsoft compiler directives are recognized and respected, if possible

But porting programs is not the whole story. You’ll want to develop new programs, test out those bugs, and for that part LSF now adds new debugging options. Of course, the trace and dump options always existed which would trace subroutine entry and exit, and allow to dump variable values to the output screen. Now there is the new -debug compiler switch with four levels: debug=1 adds code that displays the file name and source line number where a runtime error occurred; and when you press the caps lock key during execution, a window pops up where the source line numbers that are being executed flash by. At debug=2, in addition, the heap is checked at the end of each subroutine, and at level 3, after each line of source code.

Of course, you can generate symbol tables for use with SADE, to have source code level debugging.

Toolbox Calling Conventions

The Mac toolbox interface has been improved even further. Now, when you declare functions as PEXTERNAL or CEXTERNAL, character constants passed as arguments are automatically converted to the Pascal (length byte followed by text) or C format (zero-terminated string). The names of PEXTERNAL routines are always passed to the linker in upper case, regardless of the case sensitivity of the FORTRAN compiler chosen (ignore case or case-sensitive), and CEXTERNAL names are always passed in case-sensitive format. These are the formats that the linker expects for C and Pascal. You can declare variables GLOBAL, which means they are application globals referenced from A5; again, to match the Pascal and C naming conventions, you can use the PGLOBAL and CGLOBAL declarations.

System 7

As promised, the new LS FORTRAN supports AppleEvents. The runtime library includes code that automatically recognizes the four required AppleEvents, ‘oapp’, ‘odoc’, ‘pdoc’, and ‘quit’ (see this column in V7#11). If you compile a FORTRAN program with the background processing option, it will react when another program sends it an AppleEvent. As an example, I have listed two programs provided on the LSF disks: the main program opens a second application, sends it some data via an intermediate file, and the second application transfers the processed data back to the main program and quits.

The inclusion of AppleEvents in LSF opens up a whole range of perspectives: for instance, one could imagine a ‘compute server’, a Quadra for example, sitting somewhere on the network with a math library, comprising lots of tiny applications, and programs on other Macintoshes that use this library. Or a way of distributed processing on the network, where a CPU-intensive program can ‘steal’ time from other machines when they are not being used. The routine F_OpenDocWaiting() is used to synchronize such parallel processes; it will continue only when the program has received an ‘odoc’ event. A very rudimentary but effective way of parallel processing.

Although (up to now) only the four required AppleEvents are recognized automatically by the FORTRAN runtime library, you can send any event you like, as shown in the third example. HyperCard 2.1 understands the event ‘dosc’ which will make it execute a HyperTalk script contained in the event’s data. The program sets up such a script and sends it to HyperCard; if you don’t have HyperCard opened, it will issue an error message. When you have HyperCard running and start the program, you’ll hear one beep and see the card window disappear and reappear. Very impressive.

The edition manager of System 7 is also supported in a way; you can publish a FORTRAN-created file by executing CLOSE(UNIT=iunit, STATUS=’PUBLISH’). ‘Subscribing’ to such a ‘published’ document from another program that supports the edition manager means that changes made by the publisher to the document are automatically reflected in the version of the document opened by the other program (I’ll give an introduction to the Edition manager in a later column, haven’t fully under-stood it myself yet).

The last System 7 feature that has been included into LSF 3.0 is alias support. If you open an alias to a file from within a FORTRAN program, the original file will be accessed, just as you would expect.

New Compiler Options

The compiler includes support for generating 68040-specific code, and the optimizer has been improved. As far as I could tell from some limited comparisons (comparing the assembly output generated for the Linpack and Matmult benchmarks, see V7#1), the code generated for the 68040 looks extremely similar to the 68030 code, except for some floating point FMOVE instructions, which are different. I’ll check whether there is a large speed difference on a 68040 between code compiled with the -mc68030 and the -mc68040 options as soon as I have access to a Quadra.

The quality of the code has improved from version 2.1. The Linpack and matrix multiplication benchmarks (V7#1) now run at the same speed as the Absoft MacFortranII compiled versions, although the Whetstone benchmark is still 20% slower. Note, however, that Absoft is much slower if you insist on full Pascal calling conventions, which is standard in LSF.

The most striking difference between the code created by the LSF and the Absoft compiler occurred when I ran a program called “Paranoia” which tests the accuracy and consistency of math operations. While LSF at opt=3 passed all the tests with no problems reported, Absoft’s code (with the basic optimizations) reported a lot of errors and got stuck halfway through. I include the two compiled versions on the source code disk so you can see for yourself.

At this moment, LSF seems to be superior to Absoft FORTRAN in almost all aspects, from the quality of the code to the Macintosh environment, to System 7 support; there may still be a slight disadvantage for integer-computation intensive programs (not for floating point). The new Absoft FORTRAN should be out by now, so we’ll soon see what that brings. From the information they gave in their ad, especially the 68040 support looks very interesting; however, the AppleEvents support is unique to LSF.

Other Features

There are many other improvements made in LSF 3.0 that you notice browsing through the manual, most often printed in boldface text because they are nonstandard extensions. The chapter about optimization was missing from my beta manual; it would have been interesting to see what they actually changed to get the better performance, but I’ll have to wait for the final version. There is a long appendix on how to use HyperCard as a front end to FORTRAN applications, which should be especially interesting under System 7, where both HyperCard and FORTRAN programs can pass AppleEvents to each other. Of course, you can still write XCMDs in FORTRAN, as was always possible. Also, 4th Dimension external commands are supported. All in all, there is almost no reason anymore why seasoned FORTRAN programmers should learn Pascal or C (although I do like C++).

For more information, contact:

Language Systems Corporation

441 Carlisle Drive, Herndon, VA 22070-4802

800-2-LANGSYS or 703-478-0181, 703-689-9593 (fax)

AppleLink: LANGSYS, America Online: LANGSYS

Retail Price: $595 w/MPW, $495 w/o MPW

FORTRAN Upgrades: $100, MPW Upgrades: $50

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Check out the new Pirate Attack update i...
Love pirates and board games? Well, you'll love the new Pirate Attack themed update that just launched in Game of Dice. It adds a bunch of new content themed around pirates, like an all new event map based on a pirate ship which revamps the toll... | Read more »
Splash Cars guide - How to paint the tow...
Splash Cars is an arcade driving game that feels like a hybrid between Dawn of the Plow and Splatoon. In it, you'll need to drive a car around to repaint areas of a town that have lost all of their color. Check out these tips to help you perform... | Read more »
The best video player on mobile
We all know the stock video player on iOS is not particularly convenient, primarily because it asks us to hook a device up to iTunes to sync video in a world that has things like Netflix. [Read more] | Read more »
Four apps to help improve your Super Bow...
Super Bowl Sunday is upon us, and whether you’re a Panthers or a Broncos fan you’re no doubt gearing up for it. [Read more] | Read more »
LooperSonic (Music)
LooperSonic 1.0 Device: iOS Universal Category: Music Price: $4.99, Version: 1.0 (iTunes) Description: LooperSonic is a multi-track audio looper and recorder that will take your loops to the next level. Use it like a loop pedal to... | Read more »
Space Grunts guide - How to survive
Space Grunts is a fast-paced roguelike from popular iOS developer, Orange Pixel. While it taps into many of the typical roguelike sensibilities, you might still find yourself caught out by a few things. We delved further to find you some helpful... | Read more »
Dreii guide - How to play well with othe...
Dreii is a rather stylish and wonderful puzzle game that’s reminiscent of cooperative games like Journey. If that sounds immensely appealing, then you should immediately get cracking and give it a whirl. We can offer you some tips and tricks on... | Read more »
Kill the Plumber World guide - How to ou...
You already know how to hop around like Mario, but do you know how to defeat him? Those are your marching orders in Kill the Plumber, and it's not always as easy as it looks. Here are some tips to get you started. This is not a seasoned platform... | Read more »
Planar Conquest (Games)
Planar Conquest 1.0 Device: iOS Universal Category: Games Price: $12.99, Version: 1.0 (iTunes) Description: IMPORTANT: Planar Conquest is compatible only with iPad 3 & newer devices, iPhone 5 & newer. It’s NOT compatible with... | Read more »
We talk to Cheetah Mobile about its plan...
Piano Tiles 2 is a fast-paced rhythm action high score chaser out now on iOS and Android. You have to tap a series of black tiles that appear on the screen in time to the music, being careful not to accidentally hit anywhere else. Do that and it's... | Read more »

Price Scanner via MacPrices.net

BookBook For iPad Pro Coming Soon
The iPad Pro is a device unlike any other, and with Apple Pencil, it’s the ideal portable sketchpad: all that’s missing is the modern easel and portfolio to go. TwelveSouth’s BookBook for iPad Pro... Read more
12-inch 1.2GHz Silver Retina MacBook on sale...
B&H Photo has the 12″ 1.2GHz Silver Retina MacBook on sale for $1399 including free shipping plus NY sales tax only. Their price is $200 off MSRP, and it’s the lowest price for this model from... Read more
iPads on sale at Target: $100 off iPad Air 2,...
Target has WiFi iPad Air 2s and iPad mini 4s on sale for up to $100 off MSRP on their online store for a limited time. Choose free shipping or free local store pickup (if available). Sale prices for... Read more
Target offers Apple Watch for $100 off MSRP
Target has Apple Watches on sale for $100 for a limited time. Choose free shipping or free local store pickup (if available). Sale prices for online orders only, in-store prices may vary: - Apple... Read more
Apple refurbished 2014 13-inch Retina MacBook...
Apple has Certified Refurbished 2014 13″ Retina MacBook Pros available for up to $400 off original MSRP, starting at $979. An Apple one-year warranty is included with each model, and shipping is free... Read more
Macs available for up to $300 off MSRP, $20 o...
Purchase a new Mac or iPad using Apple’s Education Store and take up to $300 off MSRP. All teachers, students, and staff of any educational institution qualify for the discount. Shipping is free, and... Read more
Watch Super Bowl 50 Live On Your iPad For Fre...
Watch Super Bowl 50 LIVE on the CBS Sports app for iPad and Apple TV. Get the app and then tune in Sunday, February 7, 2016 at 6:30 PM ET to catch every moment of the big game. The CBS Sports app is... Read more
Two-thirds Of All Smart Watches Shipped In 20...
Apple dominated the smart watch market in 2015, accounting for over 12 million units and two-thirds of all shipments according to Canalys market research analysts’ estimates. Samsung returned to... Read more
12-inch 1.2GHz Retina MacBooks on sale for up...
B&H Photo has 12″ 1.2GHz Retina MacBooks on sale for $180 off MSRP. Shipping is free, and B&H charges NY tax only: - 12″ 1.2GHz Gray Retina MacBook: $1499 $100 off MSRP - 12″ 1.2GHz Silver... Read more
12-inch 1.1GHz Gray Retina MacBook on sale fo...
B&H Photo has the 12″ 1.1GHz Gray Retina MacBook on sale for $1199 including free shipping plus NY sales tax only. Their price is $100 off MSRP, and it’s the lowest price available for this model... Read more

Jobs Board

*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Subject Matter Expert - Experis (Uni...
This position is for an Apple Subject Matter Expert to assist in developing the architecture, support and services for integration of Apple devices into the domain. Read more
*Apple* Macintosh OSX - Net2Source Inc. (Uni...
…: * Work Authorization : * Contact Number(Best time to reach you) : Skills : Apple Macintosh OSX Location : New York, New York. Duartion : 6+ Months The associate would Read more
Computer Operations Technician ll - *Apple*...
# Web Announcement** Apple Technical Liaison**The George Mason University, Information Technology Services (ITS), Technology Support Services, Desktop Support Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.