Software Version: DIGITAL Fortran Version 5.2

Digital Equipment Corporation
Maynard, Massachusetts

Possession, use, or copying of the software described in this publication is authorized only pursuant to a valid written license from DIGITAL or an authorized sublicensor.

Copyright © Digital Equipment Corporation 1998, All Rights Reserved

AlphaGeneration, AXP, Bookreader, DEC, DEC Fortran, DECwindows, DIGITAL, OpenVMS, VAX, VMS, and the DIGITAL logo are trademarks of Digital Equipment Corporation, a Compaq^TM company; Compaq is a trademark of Compaq Computer Corporation.

Acrobat, Adobe, and PostScript are trademarks of Adobe Systems, Inc.
OpenMP is a trademark of the OpenMP Architecture Review Board.
OSF and OSF/1 are trademarks of the Open Software Foundation.
Microsoft, NT, Windows, and Windows NT are trademarks or registered trademarks of Microsoft Corporation in the United States and other countries.
UNIX is a registered trademark in the United States and other countries licensed exclusively through X/Open Company Ltd.

All other trademarks and registered trademarks are the property of their respective holders.

This document is available only on CD-ROM.

Contents

The previous DEC^TM Fortran and DEC Fortran 90 products are now combined into a single product called DIGITAL^TM Fortran.

DIGITAL Fortran is a multiplatform product available on the following platforms (operating system/processor architecture pairs):

Operating System	Processor	DIGITAL Fortran Product Name
DIGITAL UNIX®	Alpha	DIGITAL Fortran for DIGITAL UNIX Systems
Windows® NT®	Alpha	DIGITAL Visual Fortran, Professional Edition
Windows NT	x86	DIGITAL Visual Fortran, Standard or Professional Edition
Windows 95, Windows 98	x86	DIGITAL Visual Fortran, Standard or Professional Edition
OpenVMS TM	Alpha	DIGITAL Fortran for OpenVMS Alpha Systems
OpenVMS	VAX TM	DIGITAL Fortran 77 for OpenVMS VAX Systems 1

Product Terminology

This document uses the following product names:

• DIGITAL Fortran 90 (previously called DEC Fortran 90) supports the Fortran 95 and Fortran 90 standards, as well as earlier Fortran standards.

• DIGITAL Fortran 77 (previously called DEC Fortran) supports the FORTRAN-77 standard.

• DIGITAL Fortran refers to the combined packaging of the DIGITAL Fortran 90 and DIGITAL Fortran 77 products. DIGITAL Fortran 90 and DIGITAL Fortran 77 version numbers are now the same.

Both DIGITAL Fortran compilers recognize the Product Authorization Key (PAK) for either DIGITAL Fortran 90 or DIGITAL Fortran 77. For example, if you have a DIGITAL Fortran 77 PAK, you can begin using the DIGITAL Fortran 90 compiler (f90 command).

Contents of this Chapter:

• Online files and CD-ROM sets (see Section 1.1)
• Online documentation on the Software Product Library CD-ROM Set (see Section 1.2)
• Online release notes, reference pages, and help file (see Section 1.3)
• The DIGITAL Fortran 90 documentation set (see Section 1.4)
• The DIGITAL Fortran 77 documentation set (see Section 1.5)
• the DIGITAL Fortran Web Page (see Section 1.6)
• Ordering printed documentation (see Section 1.7)
• Documentation corrections (see Section 1.8)
• Using Internet mail for documentation feedback (see Section 1.9)

The DIGITAL Fortran documentation is available online on the two types of CD-ROM distribution devices:

• The Software Product Library (media) CD-ROM set contains the kit subsets and related documentation in ASCII and PostScript® form for DIGITAL Fortran and other layered products. This is usually called the media CD-ROM. (You can now obtain the DIGITAL Fortran product on an individual product media CD-ROM.)

• The Online Documentation Library CD-ROM set contains files in HTML, PDF, or Bookreader^TM format for DIGITAL Fortran and various forms for other layered products.

Certain DIGITAL Fortran documentation is available online in ASCII and PostScript form on the Software Product Library media CD-ROM device. These documents apply to both DIGITAL Fortran 90 and DIGITAL Fortran 77 and includes the DIGITAL Fortran:

• Installation guide
• Cover (read first) letter
• Software Product Description (SPD)

The Online Documentation Library CD-ROM you are now using includes:

• The DIGITAL Fortran 90 documentation, in HTML or PDF form.
• The DIGITAL Fortran 77 documentation, in Bookreader form.
• The common installation guide, in HTML and Bookreader form.

1.2 Software Product Library CD-ROM Online Documentation Locations

• DIGITAL Fortran installation kit subset files

• DIGITAL Fortran documentation files, including a "read first" cover letter, the installation guide, and other documentation files

• Online CD-ROM documentation files in the /readme directory on the first media CD-ROM, including a CD-ROM user guide and master list of CD products

• A cdmenu utility

To determine whether the appropriate media CD-ROM is already mounted on your system, contact the appropriate system manager.

To obtain the location of the DIGITAL Fortran documentation and kit directory on the appropriate media CD-ROM, do one of the following:

• Use the cdmenu utility provided on the media CD-ROM

• View the CD master index file on the media CD-ROM

For information about using the cdmenu utility and the files on the media CD-ROM, see the online Software Product Library CD-ROM documentation, which are provided as online files in the /readme directory on the first media CD-ROM.

For installation instructions, see the DIGITAL Fortran installation guide.

1.3 Online Release Notes, Reference Pages, and Help File

DIGITAL Fortran provides the following online information, which is copied to the user's system during installation:

• The DIGITAL Fortran 90 and DIGITAL Fortran 77 online release notes

  These provide more information on this version of DIGITAL Fortran.
  You can view the DIGITAL Fortran 77 or DIGITAL Fortran 90 release notes before installing DIGITAL Fortran once the media CD-ROM has been mounted locally. You can also select just the release notes subset using setld, allowing you to view or print the release notes before installation.

  After installation, the DIGITAL Fortran 90 online release notes are copied to:

  /usr/lib/cmplrs/fort90/relnotes90

  
  The DIGITAL Fortran 90 online release notes are also on the Online Documentation Library CD-ROM in HTML form.

  After installation, the DIGITAL Fortran 77 online release notes are copied to:

  /usr/lib/cmplrs/fort/relnotes

• DIGITAL Fortran online reference pages

  These describe the DIGITAL Fortran software components, including:

  • f90(1) (DIGITAL Fortran 90 compile and link command)
  • fsplit(1) and fpr(1) (Fortran tools)
  • intro(3f) and numerous section 3f reference pages (for the 3f language interface routines) listed in intro(3f)
  • dxml(3dxml) and numerous section 3dxml reference pages
  • intro(3hpf) and section 3hpf reference pages
  • f77(1) (DIGITAL Fortran 77 compile and link command)
  
  Use the man command to read the appropriate reference page.

• The DIGITAL Fortran help files

  Two separate online ASCII files provide DIGITAL Fortran 90 and 77 online help. These files include error message descriptions, a summary of the language elements (statements, intrinsic functions, and so on), a glossary, and other information.
  The DIGITAL Fortran 90 help file is located at:

  /usr/lib/cmplrs/fort90/decfortran90.hlp

  
  The DIGITAL Fortran 77 help file is located at:

  /usr/lib/cmplrs/fort/decfortran.hlp

  
  Use the more command or the view command to access the information available in these ASCII files. These help files are large and are not usually printed on a printer or read sequentially. For example, to view the DIGITAL Fortran 90 help file using the more command, type:

  more /usr/lib/cmplrs/fort90/decfortran90.hlp

Depending on how you order the final product, you may receive printed copies of the following DIGITAL Fortran 90 manuals:

• DIGITAL Fortran Language Reference Manual (AA-Q66SC-TK)
  This multiplatform document was revised between Version 4.1 and 5.0 (April 1997 appears on the inside title page).
  Describes the DIGITAL Fortran source language for reference purposes, including the format and use of statements, intrinsic procedures, and other language elements. Language differences among various DIGITAL Fortran 90 platforms are also identified. It also provides an overview of new Fortran 90 features (not available in FORTRAN-77).
  It identifies extensions to the Fortran 90 standard by blue-green color in the printed document and HTML files.
  This document is on the Online Documentation Library CD-ROM in HTML form and includes an index. The online HTML verison has been revised for Version 5.2.
  

• DIGITAL Fortran 90 User Manual for DIGITAL UNIX Systems (AA-Q66TC-TE)
  Last revised for Version 5.1 (March 1998 appears on the inside title page).
  Describes the DIGITAL Fortran program development and run-time environment on Digital UNIX Alpha systems, including:
  • Compiling, linking, running, and debugging DIGITAL Fortran programs
  • Comprehensive run-time performance guidelines
  • Using OpenMP^TM and DIGITAL Fortran parallel directed decomposition directives
  • Digital Fortran 90 I/O on UNIX systems
  • Run-time error-handling support and run-time messages
  • Native data type characteristics
  • Converting unformatted files in nonnative numeric formats
  • Calling other procedures and library routines (language interface)
  • Section 3f language interface (jacket) routines
  • Compatibility with Digital Fortran 77 and Digital Fortran on other Digital platforms
  • Reference information on the OpenMP and DIGITAL Fortran parallel directives and library routines
  
  This manual provides information common to DIGITAL Fortran and the DIGITAL Parallel Software Environment.
  This document is on the Online Documentation Library CD-ROM in HTML form and includes an index. The online HTML verison has been revised for Version 5.2.
  

• DIGITAL Fortran Installation Guide for DIGITAL UNIX Systems (AA-PW82E-TE)
  Revised for Version 5.2 (December 1998 appears on the inside title page).
  Explains how to install DIGITAL Fortran (DIGITAL Fortran and DIGITAL Fortran 90) on DIGITAL UNIX Alpha systems, including registering a license PAK (product authorization key), disk space and other prerequisites, and information about the DIGITAL Fortran run-time library and message file.
  This installation guide is provided in PostScript form (.ps file suffix) and in plain ASCII form (.txt suffix) on the media CD-ROM; it is also provided in HTML and Bookreader form on the Online Documentation Library CD-ROM.
  

• Digital Extended Mathematics Libarary Reference Guide (AA-RFTPA-TE)
  Revised for Version 5.2 (December 1998 appears on the inside title page).
  Describes the Digital Extended Mathematics Library, a collection of high-performance subprograms that perform different types of mathematical operations, including:
  • Matrix computations
  • Signal processing code
  • Code to solve sparse linear systems using direct and iterative methods
  
  The printed version of this document is included with the DIGITAL Fortran 90 document kit, QA-MV2AA-GZ.5.n and is on the Online Documentation Library CD-ROM in Adobe® Acrobat® PDF form.
  

• Read Before Installing or Using DIGITAL Fortran Version 5.n for DIGITAL UNIX Systems (cover letter) (AV-PW83L-TE for Version 5.2)
  Revised for Version 5.2 (December 1998).
  Provides the new features of this version of DIGITAL Fortran, the minimum operating system version, and other information. The letter contains installation information and should be read before installing DIGITAL Fortran.
  This cover letter is provided in PostScript form (.ps file suffix) and in plain ASCII form (.txt suffix) on the Software Product Library media CD-ROM set. The printed cover letter is available only with the printed documentation kit-it is not individually orderable.

You can order these documents in printed form from DIGITAL as an entire kit or individually (except for the cover letter).

Online help files are provided (see Section 1.3).

1.5 Summary of the DIGITAL Fortran 77 Documentation Set

Depending on how you order the final product, you may receive printed copies of the following DIGITAL Fortran 77 manuals:

• DEC Fortran Language Reference Manual (AA-PU45B-TK)
  Last revised for Version 3.7 (February 1995 appears on the inside title page).
  Describes the DIGITAL Fortran 77 source language for reference purposes, including the format of statements, intrinsic functions, directives, and other language elements. Extensions to the ANSI FORTRAN-77 standard are identified by blue color in the printed document and by shading in Bookreader. Language differences among various DIGITAL Fortran 77 platforms are also identified.
  In the Bookreader text window, use the View menu item Extensions to control whether extensions are displayed (as shading) or not displayed. When using Bookreader Version 4.0, note that the shading of extensions may be inaccurate.
  This document is provided in Bookreader form on the Online Documentation Library CD-ROM.
  

• DEC Fortran User Manual for DEC OSF/1 AXP^TM Systems (AA-PW81B-TK)
  Last revised for Version 3.5 (September 1994 appears on the inside title page).
  Describes the development and run-time environment on DIGITAL UNIX Alpha systems, including:
  • Compiling, linking, running, and debugging DIGITAL Fortran programs
  • Comprehensive run-time performance guidelines
  • Native data characteristics
  • Converting unformatted files in nonnative numeric formats
  • DIGITAL Fortran I/O
  • The language interface with C
  • Error handling and run-time messages
  • Native data characteristics
  • Section 3f language interface (jacket) routines
  • Compatibility with DIGITAL Fortran 77 products on other DIGITAL platforms and FORTRAN IV)
  
  This document is provided in Bookreader form on the Online Documentation Library CD-ROM.
  

• DIGITAL Fortran Installation Guide for DIGITAL UNIX Systems (AA-PW82E-TE)
  Revised for Version 5.2 (December 1998 appears on the inside title page).
  Explains how to install DIGITAL Fortran on DIGITAL UNIX Alpha systems, including registering a license PAK (product authorization key), disk space and other prerequisites, and information about the DIGITAL Fortran run-time library and message file.
  This installation guide is provided in PostScript form (.ps file suffix) and in plain ASCII form (.txt suffix) on the media CD-ROM; it is also provided in Bookreader and HTML form on the Online Documentation Library CD-ROM.
  

• Read Before Installing or Using DIGITAL Fortran Version 5.n for DIGITAL UNIX Systems (cover letter) AV-PW83L-TE for Version 5.2)
  Last revised for Version 5.2 (March 1998).
  Provides the new features of this version of DIGITAL Fortran, the minimum operating system version, and other information. The letter contains installation information and should be read before installing DIGITAL Fortran.
  This cover letter is provided in PostScript form (.ps file suffix) and in plain ASCII form (.txt suffix) on the Software Product Library media CD-ROM set. The printed cover letter is available only with the printed documentation kit-it is not individually orderable.

You can order these documents in printed form from DIGITAL as an entire kit or individually (except for the cover letter).

Online help files are provided (see Section 1.3).

1.6 DIGITAL Fortran Web Page

The DIGITAL Fortran home page provides information about DIGITAL Fortran products and software updates. You can access this page by using a Web browser to open the following Internet URL (click on the following link to view this Internet URL):

http://www.digital.com/fortran/

1.7 Ordering Printed Documentation

To order the complete printed DIGITAL Fortran 90 for Digital UNIX Systems documentation set from DIGITAL, specify the order number QA-MV2AA-GZ. To order individual DIGITAL Fortran 90 documents:

• DIGITAL Fortran Language Reference Manual (AA-Q66SC-TK)
• DIGITAL Fortran 90 User Manual for DIGITAL UNIX Systems (AA-Q66TC-TE)
• DIGITAL Fortran Installation Guide for DIGITAL UNIX Systems (AA-PW82E-TE)
• Digital Extended Mathematics Libarary Reference Guide (AA-RFTPA-TE)

To order the complete printed DIGITAL Fortran 77 for DIGITAL UNIX Systems documentation set from DIGITAL, specify the order number QA-MV2AB-GZ. To order individual DIGITAL Fortran 77 documents:

• DEC Fortran Language Reference Manual (AA-PU45B-TK)
• DEC Fortran User Manual for DEC OSF/1 AXP Systems (AA-PW81B-TK)
• DIGITAL Fortran Installation Guide for DIGITAL UNIX Systems (AA-PW82E-TE)

To order printed documentation from DIGITAL, see the "How to Order Additional Documentation" page in the back of a recently printed DIGITAL software document or use these guidelines:

• In the U.S.A., phone 1-800-344-4825 (DECdirect Sales)
• In Canada, phone 1-800-267-6215 (DECdirect Sales)
• In Puerto Rico, phone (809) 781-0505
• In other countries, contact your local DIGITAL office.

For the DIGITAL Fortran 90 documentation, any corrections are listed in the DIGITAL Fortran 90 online release notes.

For DIGITAL Fortran 77:

• In the DEC Fortran Language Reference Manual revised for Version 3.7, there are no known corrections and additions.
• In the DEC Fortran User Manual for DEC OSF/1 AXP Systems, note the following corrections and additions:
  • The Fortran preprocessor environment variable DECFORT_FPP description is inaccurate.
    The environment variable DECFORT_FPP applies only to Fortran files (not C language files). If DECFORT_FPP is set to any value, that value must be a pathname and file name of a preprocessor to be invoked instead of cpp or fpp . The DECFORT_FPP environment variable identifies the preprocessor to be invoked if the command line requests that a preprocessor be used. Setting DECFORT_FPP to a value does not invoke a preprocessor; it is only used when the command line requests a preprocessor ( cpp or fpp ).
    For those cases where the C preprocessor cpp would have been invoked for Fortran files, if you specify the f77 flag -fpp , the Fortran preprocessor fpp is invoked instead of cpp .
  • New command-line flags and language features added to DEC Fortran since Version 3.5 are not described. These new features are described in the online release notes and f77(1).

DIGITAL welcomes your comments on any DIGITAL Fortran manual or online information. You can send comments to DIGITAL in the following ways:

• Internet electronic mail: fortran_docs@zko.mts.dec.com
• FAX: 603-884-0120 Attn: Languages Documentation, ZKO2-3/K35

For the latest product information, please see the DIGITAL Fortran Web page (see Section 1.6).

Contents