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Absoft Fortran Language Reference Manual i Absoft Fortran Language Reference Manual Absoft Fortran Language Reference Manual 2781 Bond Street Rochester Hills, MI 48309 U.S.A. Tel (248) 853-0095 Fax (248) 853-0108 [email protected] i All rights reserved. No part of this publication may be reproduced or used in any form by any means, without the prior written permission of Absoft Corporation. THE INFORMATION CONTAINED IN THIS PUBLICATION IS BELIEVED TO BE ACCURATE AND RELIABLE. HOWEVER, ABSOFT CORPORATION MAKES NO REPRESENTATION OF WARRANTIES WITH RESPECT TO THE PROGRAM MATERIAL DESCRIBED HEREIN AND SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. FURTHER, ABSOFT RESERVES THE RIGHT TO REVISE THE PROGRAM MATERIAL AND MAKE CHANGES THEREIN FROM TIME TO TIME WITHOUT OBLIGATION TO NOTIFY THE PURCHASER OF THE REVISION OR CHANGES. IN NO EVENT SHALL ABSOFT BE LIABLE FOR ANY INCIDENTAL, INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE PURCHASER'S USE OF THE PROGRAM MATERIAL. U.S. GOVERNMENT RESTRICTED RIGHTS — The software and documentation are provided with RESTRICTED RIGHTS. Use, duplication, or disclosure by the Government is subject to restrictions set forth in subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at 252.227-7013. The contractor is Absoft Corporation, 2781 Bond Street, Rochester Hills, Michigan 48309. ABSOFT CORPORATION AND ITS LICENSOR(S) MAKE NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, REGARDING THE SOFTWARE. ABSOFT AND ITS LICENSOR(S) DO NOT WARRANT, GUARANTEE OR MAKE ANY REPRESENTATIONS REGARDING THE USE OR THE RESULTS OF THE USE OF THE SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY, CURRENTNESS, OR OTHERWISE. THE ENTIRE RISK AS TO THE RESULTS AND PERFORMANCE OF THE SOFTWARE IS ASSUMED BY YOU. THE EXCLUSION OF IMPLIED WARRANTIES IS NOT PERMITTED BY SOME STATES. THE ABOVE EXCLUSION MAY NOT APPLY TO YOU. IN NO EVENT WILL ABSOFT, ITS DIRECTORS, OFFICERS, EMPLOYEES OR LICENSOR(S) BE LIABLE TO YOU FOR ANY CONSEQUENTIAL, INCIDENTAL OR INDIRECT DAMAGES (INCLUDING DAMAGES FOR LOSS OF BUSINESS PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, AND THE LIKE) ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE EVEN IF ABSOFT HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. BECAUSE SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES, THE ABOVE LIMITATIONS MAY NOT APPLY TO YOU. Absoft and its licensor(s) liability to you for actual damages for any cause whatsoever, and regardless of the form of the action (whether in contract, tort, (including negligence), product liability or otherwise), will be limited to $50. Absoft, the Absoft logo, Fx, Fx2, Pro Fortran, and MacFortran are trademarks of Absoft Corporation Apple, the Apple logo, Velocity Engine, OS 9, and OS X are registered trademarks of Apple Computer, Inc. AMD64 and Opteron are trademarks of AMD Corporation CF90 is a trademark of Cray Research, Inc. IBM, MVS, RS/6000, XL Fortran, and XL C/C++ are trademarks of IBM Corp. Macintosh, NeXT, and NeXTSTEP, are trademarks of Apple Computer, Inc., used under license. MS-DOS is a trademark of Microsoft Corp. Pentium, Pentium Pro, and Pentium II are trademarks of Intel Corp. PowerPC is a trademark of IBM Corp., used under license. Sun and SPARC are trademarks of Sun Microsystems Computer Corp. UNIX is a trademark of the Santa Cruz Operation, Inc. Windows 95/98/NT/ME/2000 and XP are trademarks of Microsoft Corp. All other brand or product names are trademarks of their respective holders. Copyright © 1991-2011 Absoft Corporation and its licensor(s). All Rights Reserved Printed and manufactured in the United States of America. 1.0.1110110 i Fortran Language Reference Contents CHAPTER 1 INTRODUCTION..................................................1 Introduction to This Manual......................................................................................................................1 Introduction to Absoft Fortran..................................................................................................................1 Compatibility...............................................................................................................................................1 Conventions Used in this Manual ..............................................................................................................2 CHAPTER 2 THE FORTRAN PROGRAM .......................3 Character Set...............................................................................................................................................3 Symbolic Names ..........................................................................................................................................4 Keywords .....................................................................................................................................................4 Labels ...........................................................................................................................................................5 Statements....................................................................................................................................................5 Executable Statements..............................................................................................................................5 Nonexecutable Statements........................................................................................................................6 Statement Format......................................................................................................................................6 FORTRAN 77 Fixed Format...............................................................................................................7 Fortran 90 Free Format........................................................................................................................9 VAX FORTRAN Tab-Format...........................................................................................................10 Multiple Statement Lines........................................................................................................................10 Statement Order......................................................................................................................................11 INCLUDE Statement..............................................................................................................................11 Conditional Compilation Statements......................................................................................................12 type and KIND...........................................................................................................................................14 Data Items..................................................................................................................................................14 Constants ................................................................................................................................................15 Character Constant.............................................................................................................................15 Logical Constant................................................................................................................................16 Integer Constant.................................................................................................................................17 Alternate Integer Bases .................................................................................................................17 Real Constant.....................................................................................................................................18 Complex Constant .............................................................................................................................19 Hollerith Constant..............................................................................................................................19 Variables.................................................................................................................................................19 Substrings ...............................................................................................................................................20 Storage........................................................................................................................................................20 Numeric Storage Unit.............................................................................................................................21 Character Storage Unit ...........................................................................................................................21 ii Storage Sequence................................................................................................................................... 21 Storage Association ............................................................................................................................... 21 Storage Definition.................................................................................................................................. 22 CHAPTER 3 SPECIFICATION AND DATA
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