Introducing Fortran 95

472 Pages·2000·27.925 MB·English

by  Ian Chivers BSc, PGCEd, MSc, Jane Sleightholme MSc (auth.)

Introducing Fortran 95
Springer-Verlag London Ltd.
Ian Chivers and Jane Sleightholme
Introducing
Fortran 95
Springer
Ian Chivers, BSc, PGCEd, MSc
Jane Sleightholme, MSc
The Computer Centre, Kings College Strand Campus, London WC2R 2LS, UK
ISBN 978-1-85233-276-1
British Library Cataloguing in Publication Data
Chivers, I. D. (Ian David), 1952-
Introducing Fortran 95
1. Fortran 95 (Computer language)
I. Title II. Sleightholme, Jane
005.1' 33
ISBN 978-1-85233-276-1
Library of Congress Cataloging-in-Publication Data
Chivers, I. D. (Ian David), 1952-
Introducing Fortran 95 / Ian Chivers and Jane Sleightholme
p. cm.
Includes bibliographical references and index.
ISBN 978-1-85233-276-1 ISBN 978-1-4471-0403-2 (eBook)
DOI 10.1007/978-1-4471-0403-2
1. Fortran 95 (Computer program language) I. Sleightholme, Jane, 1950 -II. Title.
QA76.73.F29 C482000
005.13' 3—dc21
00-034505
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© Springer-Verlag London 2000
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Contents v
1 Overview ...........••.•. 1
1.1 Miscellanea . . . . . . . . . . . . 7
2 Introduction to Computer Systems 9
2.1 The core of a computer system . .10
2.1.1 Central Processor Unit - CPU .10
2.1.2 Memory ........... . .10
2.1.3 Bus ............. . .10
2.2 Other components of a computer system .11
2.2.1 Disks .11
2.2.2 Others .11
2.3 Software · 13
2.4 Problems · 14
2.5 Bibliography · 14
3 Introduction to Operating Systems .. 15
3.1 History of operating systems . .16'
3.l.l The 1940s . .16
3.1.2 The 1950s ...... . .16
3.1.3 The 1960s ...... . .16
3.1.4 The 1960s and 1970s . .16
3.1.5 The 1970s, 1980s and 1990s . .17
3.2 Networking . .17
3.3 Problems ............ . · 18
3.4 Bibliography . . . . . . . . . . . · 18
4 Introduction to Using a Computer System . . .19
4.1 Files ........ . .20
4.2 Editors ...... . .20
4.3 Single user systems . .20
4.4 Networked systems. .20
4.5 Multi-user systems . .21
4.6 Other useful things to know .21
4.7 Bibliography . . . . . . . . .22
5 Introduction to Problem Solving .••. 23
5.1 Naturallanguage . .24
5.2 Artificial language .25
5.2.1 Notations .25
5.3 Resume .... .25
5.4 Algorithms . . .26
5.4.1 Top-down. .26
5.4.2 Bottom-up. .26
5.4.3 Stepwise refinement .27
5.4.4 Modular programming .27
vi Contents
5.4.5 Object oriented programming . . . . . ..... 28
5.5 Systems analysis and design . . . . . . . . ..... 28
5.5.1 Problem definition . . . . . . . . .28
5.5.2 Feasibility study and fact finding · . 29
5.5.3 Analysis ... . · .29
5.5.4 Design .... . · .29
5.5.5 Detailed design .29
5.5.6 Implementation .29
5.5.7 Evaluation and testing .29
5.5.8 Maintenance .30
5.6 Conclusions . .30
5.7 Problems .... .30
5.8 Bibliography . . .31
6 Introduction to Programming Languages ................ 33
6.1 Some early theoretical work . . . . . . . . . . . . . . . . . . . 34
6.2 What is a programming language? . . . . . . . . 34
6.3 Program language development and engineering . 34
6.4 The early days . . 34
6.4.1 Fortran .35
6.4.2 Cobol . . . . .35
6.4.3 Algol .... .36
6.5 Chomsky and program language development . 37
6.6 Lisp. . . . . . . . . . . . . . .37
6.7 Snobol. . . . . . . . . . . . . .38
6.8 Second generation languages . . 38
6.8.1 PU1 and Algol 68 . . . 38
6.8.2 Simula. .38
6.8.3 Pascal .38
6.8.4 APL . .39
6.8.5 Basic .39
6.8.6 C. . . .39
6.9 Some other strands in language development . . . .40
6.9.1 Abstraction, stepwise refinement and modules · .40
6.9.2 Structured programming. . . . . . .40
6.9.3 Standardization . . .40
6.10 Ada .. . .41
6.11 Modula ....... . .41
6.12 Modula 2 ...... . .41
6.13 Other language developments . .42
6.13.1 Logo ............ . .42
6.13.2 Postscript, TeX and LaTeX .43
6.13.3 Prolog ........... . · .43
Contents vii
6.13.4 SQL ................ . .43
6.13.5 ICON ............... . .43
6.14 Object orientated programming - OOP .44
6.14.1 Oberon and Oberon 2 .44
6.14.2 Smalltalk .45
6.14.3 C++ .... . .45
6.15 Fortran 90 ... . .46
6.15.1 Fortran 1995 .46
6.15.2 ISO Technical Reports TR15580 and TR15581 . .47
6.15.3 High Performance Fortran - HPF .47
6.15.4 Internet resources . .48
6.16 Summary ................ . .49
6.17 Bibliography . . . . . . . . . . . . . . . .49
7 Introduction to Programming . . . . . . . . . . . . . . . . . . . . . . . SS
7.1 Language standardisation . 56
7.1.1 Fortran 66. . 56
7.1.2 Fortran 77 . . . . . 56
7.1.3 Fortran 90 . . . . . 56
7.1.3.1 Source form . . 56
7.1.3.2 Control structures . . 56
7.1.3.3 Numeric precision .57
7.1.3.4 Array processing . . . .57
7.1.3.5 Dynamic behaviour . . . .57
7.1.3.6 User defined data types and operators. .57
7.1.3.7 Procedures . . . . . . .57
7.1.3.8 Modules. .57
7.1.4 Fortran 95 ... .57
7.1.5 Fortran 2000 . .58
7.2 Language strengths and weaknesses . . . . .58
7.3 Elements of a programming language . . . . . . . . . .58
7.3.1 Data description statements .. .59
7.3.2 Control structures . . . . . . . . . . . . . . . . . . ...... 59
7.3.3 Data processing statements . . . . .59
7.3.4 Input and output (110) statements .59
7.4 Variables - name, type and value .. · .61
7.5 Notes ................ . · .63
7.6 Some more Fortran rules . . . . . . . · .64
7.7 Good programming guidelines . . . · .65
7.8 Fortran character set . . . .65
7.8.1 Notes ...... . .66
7.8.2 Compilers .... . .66
7.9 Program development .67
viii Contents
7.10 Problems. . . . . . . . . . . . . . . . . . ... 68
8 Arithmetic . . • • • . . • • • • • . . • . . • . . •• 69
8.1 Rounding and truncation . . . . . . . . .. ... . . .73
8.2 Example 1: Time taken for light to travel from the Sun to Earth .74
8.3 The PARAMETER statement . . . . . . . . . . . . . . . . . . . .76
8.4 Precision and size of numbers . . . . . . . . . . . . . . . . . . . .77
8.5 Health warning: optional reading, beginners are advised to leave
until later . . . . . . . . . . . . . . . . .79
8.5.1 Selecting different INTEGER kinds . . . . . . . . . . . . . .81
8.5.2 Selecting different REAL kinds . . . . . . . . . . . . . . . .82
8.5.3 Specifying kind types for literal integer and real constants . .82
8.5.4 Positional number systems . . . . . . . . . .83
8.5.5 Bit data type and representation model . . .83
8.5.6 Integer data type and representation model .84
8.5.7 Real data type and representation model . .84
8.5.8 IEEE 754 ................. . .85
8.5.9 Example 2: Testing the numerical representation of different
kind types on a system . . . . . . . . . . . . . . . . . . . . . .85
8.5.10 Example 3: Binary representation of different integer kind type
numbers ........................ . .89
8.5.11 Summary of how to select the appropriate KIND type .91
8.6 Variable status .91
8.7 Summary .. .91
8.8 Problems ... .92
8.9 Bibliography . .95
9 Arrays 1: Some Fundamentals ..••... .97
9.1 Tables of data. . . . . . .98
9.1.1 Telephone directory ..... .98
9.1.2 Book catalogue . . . . . . . . .98
9.1.3 Examination marks or results .99
9.1.4 Monthly rainfall .... .99
9.2 Arrays in Fortran . . . . . . 100
9.3 The DIMENSION attribute 100
9.4 An index .... 101
9.5 Control structure . . . . 101
9.6 Monthly rainfall .... 101
9.6.1 Example 1: Rainfall 102
9.7 People's weights .... 103
9.7.1 Example 2: People's weights. 104
9.8 Summary 105
9.9 Problems ........•.... 106
Contents ix
10 Arrays 2: Further Examples • . . 109
1O.l Higher dimension arrays . . . . 110
10.1.1 Example 1: A map . . . . . . . . . . . 110
10.1.2 Example 2: Sensible tabular output . . . . . 112
10.1.3 Example 3: Average of three sets of values . 112
10.1.4 Example 4: Booking arrangements in a theatre or cinema 114
10.2 Additional forms of the DIMENSION attribute and DO loop
statement ................... . 115
10.2.1 Example 5: Voltage from -20 to +20 volts 115
10.2.2 Example 6: Longitude from -180 to + 180 . 116
10.2.3 Notes ............... . 116
10.3 The DO loop and straight repetition . . . . . . 116
10.3.1 Example 7: Table of temperatures . . . . . 116
10.3.2 Example 7: Means and standard deviations 117
10.4 Summary .................. . 118,
10.5 Problems .................. . 119
11 Whole Array and Additional Array Features 123
11.1 Terminology 124
11.1.1 Rank .. 124
11.1.2 Bounds 124
11.1.3 Extent 124
11.1.4 Size .. 124
11.1.5 Shape . 124
11.1.6 Conformable 124
11.2 Whole array manipulation 124
11.2.1 Assignment 125
11.2.2 Expressions . . . 125
11.3 Array sections ... 127
11.3.1 Example 1: Ages 127
11.3.2 Example 2: Examination results 127
11.4 Allocatable arrays ........ . 127
11.4.1 Example 3: Height above sea level 128
11.5 Array element ordering. . . . . . . . . 129
11.5.1 Array element ordering and physical and virtual memory 130
11.6 Array constructors . . . . . . . . . . . . . . . . . . 130
11.7 Masked array assignment and the where statement . 131
11.7.1 Notes ..................... . 132
11.8 The FORALL statement and FORALL construct . 132
11.8.1 Syntax . 133
11.9 Summary .. 133
11.10 Problems .. 133
11.11 Bibliography 134
x Contents
12 Output of Results • . . . . . . 135
12.1 Integers, I fonnat . 136
12.2 Reals, F fonnat 137
12.2.1 Litres to Pints . 138
12.2.2 Pints To Litres 138
12.3 Reals, E fonnat 138
12.3.1 Simple E fonnat example 140
12.4 Spaces ........... . 140
12.5 Alphanumeric or character fonnat, A 141
12.5.1 Headings ............ . 141
12.6 Mixed type output in a FORMAT statement 142
12.7 Common mistakes . . . . 142
12.8 OPEN (and CLOSE) ... 143
12.8.1 The OPEN statement 143
12.8.2 Writing ..... . 144
12.9 Repetition . . . .. . . . 145
12.10 Some more examples . . 147
12.11 Implied DO loops and array sections for array output 148
12.12 Fonnatting for a line-printer . . . . . . . . . . . . . . 151
12.12.1 Mechanics of carriage control . . . . . . . . . . . 152
12.12.2 Generating a new line, on both line-printers and tenninals . 153
12.13 Summary ... . 153
12.14 Problems ....................... . 154
13 Reading in Data . . . . . . . . . . . . . . . . . . . . . . 157
13.1 Reading from the terminal versus reading from files 158
13.2 Fixed fields on input . . . . . . 158
13.2.1 Integers, the I fonnat . . . . 158
13.2.2 Reals, the F and E fonnats 158
13.3 Blanks, nulls and zeros 161
13.4 Characters. . . . . . . . . 162
13.5 Skipping spaces and lines 162
13.6 Reading ........ . 163
13.7 File manipulation again 163
13.8 Errors when reading 164
13.9 Summary ....... . 165
13.10 Problems ....... . 165
14 Functions .......................... . 167
14.1 An introduction to predefined functions and their use 168
14.1.1 Example 1: Simple function usage. . . 169
14.2 Generic functions . . . . . . . . . . . . . . 169
14.2.1 Example 2: The ABS generic function 170
14.3 Elemental functions ........... . 170