Fortran 95 Language Guide

Fortran is one of the most widely used programming languages in science and engineering. Fortran 90 replaced the outmoded FORTRAN 77 in 1991 and this recent version of the International Standard enhances this version. It also includes several new features to ensure that Fortran continues to be aligned with High Performance Fortran (HPF) for parallel computer architectures. <br><b>Fortran 95 Language Guide</b> will serve as a language reference manual for programmers, provide teaching material for introductory courses in Fortran programming, and give help to experienced Fortran programmers migrating to the new standard. Gehrke has provided a comprehensive and easy-to-understand description of the Fortran 95 programming language as defined by the ISO, which will be welcomed by both practitioners and students alike.

1. Source Form.- 1.1 Fixed Source Form.- 1.2 Free Source Form.- 1.3 Embedding of Program Lines by INCLUDE.- 1.4 Classification of Fortran Statements.- 1.5 Statement Ordering.- 2 Type Concept.- 2.1 Intrinsic Types.- 2.1.1 Integer Type.- 2.1.2 Real Type and Double Precision Real Type.- 2.1.3 Complex Type.- 2.1.4 Logical Type.- 2.1.5 Character Type.- 2.2 Derived Types.- 2.2.1 Derived Type Definition.- 2.2.1.1 Type Component Definition.- 2.2.1.2 Private and Public Derived Type Definitions.- 2.2.2 Structure Objects.- 3 Lexical Tokens.- 3.1 Scoping Units.- 3.2 Keywords.- 3.3 Names.- 3.4 Operators and Assignment Symbol.- 3.5 Statement Labels.- 3.6 Literal Constants.- 3.6.1 Integer Literal Constants.- 3.6.2 Real Literal Constants.- 3.6.3 Double Precision Real Literal Constants.- 3.6.4 Complex Literal Constants.- 3.6.5 Logical Literal Constants.- 3.6.6 Character Literal Constants.- 3.6.7 Binary, Octal, and Hexadecimal Literal Constant.- 4 Data Objects.- 4.1 Constants.- 4.2 Variables.- 4.3 Scalars.- 4.3.1 Character Substrings.- 4.4 Arrays.- 4.4.1 Inner Structure of Arrays.- 4.5 Structure Components.- 4.6 Automatic Variables.- 4.7 Association.- 4.7.1 Name Association.- 4.7.2 Pointer Association.- 4.7.3 Storage Association.- 4.8 Definition Status.- 5 Pointers.- 5.1 Pointer Processing.- 5.1.1 Creation of Pointer Targets.- 5.1.2 Association Status.- 5.1.3 Deallocation of Pointer Targets.- 5.1.4 Nullification of Pointer Associations.- 6 Array Processing.- 6.1 Array Declaration.- 6.1.1 Explicit-Shape Arrays.- 6.1.2 Assumed-Shape Arrays.- 6.1.3 Assumed-Size Arrays.- 6.2 Reference and Use.- 6.2.1 Whole Arrays.- 6.2.2 Array Elements.- 6.2.3 Array Sections.- 6.2.3.1 Subscript-Triplet.- 6.2.3.2 Vector-Subscript.- 6.2.3.3 Array Sections of Substrings.- 6.3 Memory Management and Dynamic Control.- 6.3.1 Automatic Arrays.- 6.3.2 Allocatable Arrays.- 6.3.3 Array Pointers.- 6.4 Construction of Array Values.- 6.5 Operations on Arrays.- 6.5.1 Array Expressions.- 6.5.2 Array Subprograms.- 6.5.3 Array Assignments.- 7 Expressions.- 7.1 Numeric Intrinsic Expressions.- 7.2 Relational Intrinsic Expressions.- 7.2.1 Numeric Relational Intrinsic Expressions.- 7.2.2 Character Relational Intrinsic Expressions.- 7.3 Logical Intrinsic Expressions.- 7.4 Character Intrinsic Expressions.- 7.5 Defined Expressions.- 7.5.1 Defined Operators and Extended Intrinsic Operators.- 7.5.1.1 Nonextended Defined Operator.- 7.5.1.2 Extended Defined Operator.- 7.5.1.3 Extended Intrinsic Operator.- 7.6 Common Rules for Expressions.- 7.6.1 Precedence of Operators.- 7.6.2 Interpretation of Expressions.- 7.6.3 Evaluation of Expressions.- 7.7 Special Expressions.- 7.7.1 Constant Expressions.- 7.7.2 Initialization Expressions.- 7.7.3 Specification Expressions.- 8 Assignments.- 8.1 Intrinsic Assignment Statements.- 8.1.1 Numeric Assignment Statement.- 8.1.2 Logical Assignment Statement.- 8.1.3 Character Assignment Statement.- 8.1.4 Assignment Statement for Derived Types.- 8.2 Defined Assignment Statements.- 8.2.1 Nonextended Defined Assignment.- 8.2.2 Extended Defined Assignment.- 8.3 Pointer Assignment Statement.- 8.4 Masked Array Assignments.- 8.4.1 WHERE Statement.- 8.4.2 WHERE Construct.- 8.4.3 Common Rules for Masked Array Assignments.- 8.5 Indexed Assignments.- 8.5.1 FORALL Statement.- 8.5.1.1 Execution of the FORALL Statement.- 8.5.2 FORALL Construct.- 8.5.3 Common Rules for Indexed Assignments.- 9 Declarations and Specifiactions.- 9.1 Attributes.- 9.1.1 ALLOCATABLE Attribute.- 9.1.2 DATA Attribute.- 9.1.3 DIMENSION Attribute.- 9.1.4 EXTERNAL Attribute.- 9.1.5 INTENT Attribute.- 9.1.6 INTRINSIC Attribute.- 9.1.7 OPTIONAL Attribute.- 9.1.8 PARAMETER Attribute.- 9.1.9 POINTER Attribute.- 9.1.10 PRIVATE Attribute.- 9.1.11 PUBLIC Attribute.- 9.1.12 SAVE Attribute.- 9.1.13 TARGET Attribute.- 9.2 Type Declaration Statements.- 9.2.1 INTEGER Statement.- 9.2.2 REAL Statement.- 9.2.3 DOUBLE PRECISION Statement.- 9.2.4 COMPLEX Statement.- 9.2.5 LOGICAL Statement.- 9.2.6 CHARACTER Statement.- 9.2.6.1 Character Length.- 9.2.7 TYPE Declaration Statement.- 9.3 Attribute Specification Statements.- 9.3.1 ALLOCATABLE Statement.- 9.3.2 DATA Statement.- 9.3.2.1 Implied-DO.- 9.3.3 DIMENSION Statement.- 9.3.4 EXTERNAL Statement.- 9.3.5 INTENT Statement.- 9.3.6 INTRINSIC Statement.- 9.3.7 OPTIONAL Statement.- 9.3.8 PARAMETER Statement.- 9.3.9 POINTER Statement.- 9.3.10 PRIVATE Statement.- 9.3.11 PUBLIC Statement.- 9.3.12 SAVE Statement.- 9.3.13 TARGET Statement.- 9.4 Additional Specification Statements.- 9.4.1 COMMON Statement.- 9.4.2 EQUIVALENCE Statement.- 9.4.2.1 EQUIVALENCE and COMMON.- 9.4.3 IMPLICIT Statement.- 9.4.4 NAMELIST Statement.- 10 EXECUTION CONTROL.- 10.1 GOTO Statements.- 10.1.1 Unconditional GO TO Statement.- 10.1.2 Computed GO TO Statement.- 10.2 IF Statements.- 10.2.1 Arithmetic IF Statement.- 10.2.2 Logical IF Statement.- 10.3 IF Construct.- 10.3.1 Simple IF Constructs.- 10.3.2 Nested IF Constructs.- 10.4 CASE Construct.- 10.4.1 Simple CASE Constructs.- 10.5 DO Construct.- 10.5.1 DO Statement.- 10.5.2 Do-Termination Statement.- 10.5.3 Forms of DO Constructs.- 10.5.4 Execution of a DO Construct.- 10.5.4.1 Additional Details about Count Loops.- 10.5.4.2 Additional Details about WHILE Loops.- 10.5.4.3 Additional Details about Endless Loops.- 10.5.4.4 CYCLE Statement and EXIT Statement.- 10.5.5 Nested DO Constructs.- 10.6 Nested Constructs.- 10.7 CONTINUE Statement.- 10.8 STOP Statement.- 10.9 CALL, END, and RETURN Statements.- 11 Input/Output.- 11.1 Records.- 11.2 Files.- 11.3 File Attributes of External Files.- 11.3.1 File Names.- 11.3.2 Access Methods.- 11.3.2.1 Sequential Access.- 11.3.2.2 Direct Access.- 11.3.3 Form of a File.- 11.3.4 File Position.- 11.4 Units.- 11.5 Preconnected Units and Predefined Files.- 11.6 Input/Output Statements.- 11.6.1 Input/Output Specifiers.- 11.6.1.1 UNIT=Specifier.- 11.6.1.2 FMT= Specifier.- 11.6.1.3 NML= Specifier.- 11.6.1.4 REC= Specifier.- 11.6.1.5 ADVANCE= Specifier.- 11.6.1.6 End-of-Record Condition and EOR= Specifier.- 11.6.1.7 IOSTAT= Specifier.- 11.6.1.8 Error Conditions and ERR= Specifier.- 11.6.1.9 End-of-File Condition and END= Specifier.- 11.6.1.10 SIZE= Specifier.- 11.6.2 Input/Output Lists.- 11.6.2.1 Implied-DO.- 11.6.3 Data Transfer Statements.- 11.6.3.1 Formatted Input/Output.- 11.6.3.2 Unformatted Input/Output.- 11.6.3.3 List-Directed Input/Output.- 11.6.3.4 Internal Input/Output.- 11.6.3.5 Namelist Input/Output.- 11.6.3.6 Nonadvancing Input/Output.- 11.6.3.7 Printing.- 11.6.4 File Status Statements.- 11.6.4.1 OPEN Statement.- 11.6.4.2 CLOSE Statement.- 11.6.4.3 INQUIRE Statement.- 11.6.5 File Positioning Statements.- 12 Formats.- 12.1 Format Specification.- 12.1.1 Format Specification in FORMAT Statement.- 12.2.2 Character Format Specification.- 12.2 Interaction between Input/Output List and Format.- 12.2.1 Repeat Specification, Groups of Edit Descriptors.- 12.2.2 Reversion of Format Control.- 12.3 Edit Descriptors.- 12.3.1 A Edit Descriptors.- 12.3.2 B Edit Descriptors.- 12.3.3 BN and BZ Edit Descriptors.- 12.3.4 Character Constant Edit Descriptors.- 12.3.5 Colon Edit Descriptor.- 12.3.6 D Edit Descriptor.- 12.3.7 E Edit Descriptors.- 12.3.8 EN Edit Descriptors.- 12.3.9 ES Edit Descriptors.- 12.3.10 F Edit Descriptor.- 12.3.11 G Edit Descriptors.- 12.3.12 I Edit Descriptors.- 12.3.13 L Edit Descriptor.- 12.3.14 O Edit Descriptors.- 12.3.15 P Edit Descriptor, Scale Factor.- 12.3.16 Sign Control Edit Descriptors.- 12.3.17 Slash Edit Descriptor.- 12.3.18 Tabulator Edit Descriptors.- 12.3.19 X Edit Descriptor.- 12.3.20 Z Edit Descriptors.- 13 Progrm Units and Subprogrmas.- 13.1 Main Program.- 13.2 Modules.- 13.2.1 USE Statement.- 13.3. Block Data Program Units.- 13.4 Subprograms.- 13.4.1 User-Defined Functions (except Statement Functions).- 13.4.1.1 Function Definition.- 13.4.1.2 Explicit Invocation, Function Reference.- 13.4.1.3 Operator Functions.- 13.4.2 User-Defined Subroutines.- 13.4.2.1 Subroutine Definition.- 13.4.2.2 Explicit Invocation, CALL Statement.- 13.4.2.3 Assignment Subroutines.- 13.4.3 External Subprograms.- 13.4.4 Internal Subprograms.- 13.4.5 Module Subprograms.- 13.4.6 Dummy Subprograms.- 13.4.7 Statement Functions.- 13.4.7.1 Statement Function Definition.- 13.4.7.2 Invocation of a Statement Function.- 13.4.8 Interface Blocks.- 13.4.9 Overloaded Generic Subprogram Names.- 13.4.10 Additional Entry Points, ENTRY Statement.- 13.4.11 Return from the Invoked Subprogram.- 13.5 Internal Program Communication.- 13.5.1 Argument Lists.- 13.5.1.1 Dummy Argument List.- 13.5.1.2 Actual Argument List.- 13.5.2 Argument Association.- 13.5.2.1 Data Objects as Dummy Arguments.- 13.5.2.2 Implicit Association of Two Dummy Arguments.- 13.5.2.3 Length of Character Dummy Arguments.- 13.5.2.4 Scalar Arguments.- 13.5.2.5 Dummy (Argument) Arrays.- 13.5.2.6 Dummy (Argument) Pointers.- 13.5.2.7 Sequence Association.- 13.5.2.8 Assumed-Size Arrays.- 13.5.2.9 Assumed-Shape Arrays.- 13.5.2.10 Restrictions on the Association of Data Entities.- 13.5.2.11 Dummy Subprograms.- 13.5.2.12 Asterisk Dummy Arguments.- 13.5.3 Optional Dummy Arguments.- 13.5.4 Dummy Argument with INTENT Attribute.- 13.5.5 Common Blocks.- 14 Intrinsic Subprograms.- 14.1 Intrinsic Functions.- 14.1.1 Table of Intrinsic Functions.- 14.2 Intrinsic Subroutines.- 14.3 Intrinsic Subprogram Reference.- 14.4 Intrinsic Subprogram Definitions.- 14.4.1 Descriptions.- A Character Sets and Collating Sequences A-1.- A.1 Processor-Dependent Character Sets A-1.- A.2 ASCII Character Set A-1.- B MODELS FOR NUMBERS B-1.- B.1 Models for Integers B-1.- B.2 Models for Reals B-1.- B.3 Models for Bit Manipulation B-2.- C DECREMENTAL LANGUAGE FEATURES C-1.- C.1 Deleted Language Features C-1.- C.2 Obsolescent Language Features C-2.- D INDEX D-1.