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Portions © Copyright 2001 Hewlett-Packard Development Company, L.P. ii Contents About This Manual Product Website and Support .................................................................. xxvi Related Publications................................................................................. xxvii Conventions .............................................................................................. xxx Platform Labels.................................................................................... xxxii Chapter 1 Overview Language Standards Conformance .......................................................... 1-2 Language Compatibility............................................................................. 1-2 New Language Features ........................................................................... 1-2 Fortran 2003 Features............................................................................... 1-3 Improved Features................................................................................ 1-3 Fortran 95 Features................................................................................... 1-3 New Features ....................................................................................... 1-3 Improved Features................................................................................ 1-5 Fortran 90 Features................................................................................... 1-6 New Features ....................................................................................... 1-6 Improved Features................................................................................ 1-8 Chapter 2 Program Structure, Characters, and Source Forms Program Structure..................................................................................... 2-1 Statements ........................................................................................... 2-2 Names .................................................................................................. 2-4 Character Sets .......................................................................................... 2-5 Source Forms............................................................................................ 2-6 iii Intel Fortran Language Reference Free Source Form................................................................................. 2-9 Fixed and Tab Source Forms.............................................................. 2-11 Fixed-Format Lines ........................................................................ 2-13 Tab-Format Lines ........................................................................... 2-13 Source Code Useable for All Source Forms ....................................... 2-15 Chapter 3 Data Types, Constants, and Variables Intrinsic Data Types ................................................................................... 3-2 Integer Data Types................................................................................ 3-4 Real Data Types.................................................................................... 3-6 General Rules for Real Constants.................................................... 3-7 REAL(4) Constants .......................................................................... 3-8 REAL(8) or DOUBLE PRECISION Constants ................................. 3-9 REAL(16) Constants ...................................................................... 3-10 Complex Data Types........................................................................... 3-10 General Rules for Complex Constants........................................... 3-11 COMPLEX(4) Constants................................................................ 3-11 COMPLEX(8) or DOUBLE COMPLEX Constants ......................... 3-12 COMPLEX(16) Constants.............................................................. 3-13 Logical Data Types.............................................................................. 3-14 Character Data Type........................................................................... 3-14 C Strings in Character Constants................................................... 3-16 Character Substrings .................................................................... 3-17 Derived Data Types ................................................................................. 3-19 Derived-Type Definition....................................................................... 3-20 Default Initialization............................................................................. 3-22 Structure Components........................................................................ 3-23 Structure Constructors........................................................................ 3-26 Binary, Octal, Hexadecimal, and Hollerith Constants .............................. 3-28 Binary Constants ................................................................................ 3-28 Octal Constants .................................................................................. 3-29 Hexadecimal Constants ...................................................................... 3-29 Hollerith Constants ............................................................................. 3-30 Determining the Data Type of Nondecimal Constants ........................ 3-31 iv Contents Variables .................................................................................................. 3-33 Data Types of Scalar Variables ........................................................... 3-34 Specification of Data Type.............................................................. 3-34 Implicit Typing Rules....................................................................... 3-35 Arrays.................................................................................................. 3-35 Whole Arrays.................................................................................. 3-38 Array Elements............................................................................... 3-38 Array Sections ................................................................................ 3-41 Array Constructors.......................................................................... 3-44 Chapter 4 Expressions and Assignment Statements Expressions ............................................................................................... 4-1 Numeric Expressions ............................................................................ 4-2 Using Parentheses in Numeric Expressions .................................... 4-4 Data Type of Numeric Expressions .................................................. 4-5 Character Expressions.......................................................................... 4-6 Relational Expressions.......................................................................... 4-7 Logical Expressions .............................................................................. 4-8 Data Types Resulting from Logical Operations ................................ 4-9 Evaluation of Logical Expressions.................................................... 4-9 Defined Operations ............................................................................