Object-oriented programming via Fortran 90-95

301 Pages·2003·1.15 MB·English

by  Ed Akin

O O P
bject riented rogramming
F
via ortran 90/95
Ed Akin
RiceUniversity
MechanicalEngineeringand MaterialsScience Department
Houston,Texas
May29,2001
Draft#4.2, Copyright c2001, Allrightsreserved.
(cid:13)
ii
Contents
Preface vii
1 ProgramDesign 1
1.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2. ProblemDefinition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3. ModularProgramDesign . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.4. ProgramComposition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.4.1. Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.4.2. Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.4.3. FlowControl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.4.4. Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.4.5. Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.4.6. DynamicMemoryManagement . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.5. Programevaluationandtesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.6. Programdocumentation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
1.7. ObjectOrientedFormulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
1.8. Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2 DataTypes 23
2.1. IntrinsicTypes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.2. UserDefinedDataTypes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.3. AbstractDataTypes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2.4. Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.5. Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3 ObjectOrientedProgrammingConcepts 33
3.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.2. Encapsulation,Inheritance,andPolymorphism . . . . . . . . . . . . . . . . . . . . . 34
3.2.1. ExampleDate,Person,andStudentClasses . . . . . . . . . . . . . . . . . . . 37
3.3. ObjectOrientedNumericalCalculations . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.3.1. ARationalNumberClassandOperatorOverloading . . . . . . . . . . . . . . 39
3.4. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
3.5. Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4 FeaturesofProgrammingLanguages 51
4.1. Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
4.2. StatementsandExpressions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.3. FlowControl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
4.3.1. ExplicitLoops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
4.3.2. ImpliedLoops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
4.3.3. Conditionals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
4.4. Subprograms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
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4.4.1. FunctionsandSubroutines . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
4.4.2. GlobalVariables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
4.4.3. BitFunctions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.4.4. ExceptionControls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.5. InterfacePrototype . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
4.6. CharactersandStrings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
4.7. UserDefinedDataTypes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
4.7.1. OverloadingOperators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
4.7.2. UserDefinedOperators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
4.8. PointersandTargets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
4.8.1. PointerTypeDeclaration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
4.8.2. PointerAssignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
4.8.3. UsingPointersinExpressions . . . . . . . . . . . . . . . . . . . . . . . . . . 88
4.8.4. PointersandLinkedLists. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
4.9. AccessingExternalSourceFilesandFunctions . . . . . . . . . . . . . . . . . . . . . 89
4.10.ProceduralApplications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
4.10.1. FittingCurvestoData . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
4.10.2. Sorting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
4.11.Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
5 ObjectOrientedMethods 103
5.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
5.2. TheDrillClass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
5.3. GlobalPositioningSatelliteDistances . . . . . . . . . . . . . . . . . . . . . . . . . . 106
5.4. Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
6 InheritanceandPolymorphism 119
6.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
6.2. ExampleApplicationsofInheritance . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
6.2.1. TheProfessorClass. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
6.2.2. TheEmployeeandManagerClasses . . . . . . . . . . . . . . . . . . . . . . . 121
6.3. Polymorphism. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
6.3.1. Templates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
6.3.2. SubtypingObjects(DynamicDispatching) . . . . . . . . . . . . . . . . . . . 130
6.4. Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
7 OODataStructures 135
7.1. DataStructures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
7.2. Stacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
7.3. Queues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
7.4. LinkedLists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
7.4.1. SinglyLinkedLists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
7.4.2. DoublyLinkedLists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
7.5. Direct(Random)AccessFiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
7.6. Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
8 ArraysandMatrices 155
8.1. SubscriptedVariables:Arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
8.1.1. InitializingArrayElements. . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
8.1.2. IntrinsicArrayFunctions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
8.1.3. ColonOperationsonArrays(SubscriptTriplet) . . . . . . . . . . . . . . . . . 159
8.1.4. ArrayLogicalMaskOperators . . . . . . . . . . . . . . . . . . . . . . . . . . 163
8.1.5. UserDefinedOperators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
8.1.6. ConnectivityListsandVectorSubscripts . . . . . . . . . . . . . . . . . . . . 166
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8.1.7. ComponentGatherandScatter . . . . . . . . . . . . . . . . . . . . . . . . . . 168
8.2. Matrices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
8.2.1. MatrixAlgebra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
8.2.2. Inversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
8.2.3. Factorizations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
8.2.4. DeterminantofaMatrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
8.2.5. MatrixCalculus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
8.2.6. ComputationwithMatrices . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
8.3. Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
9 AdvancedTopics 181
9.1. Templates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
9.2. SubtypingObjects(DynamicDispatching) . . . . . . . . . . . . . . . . . . . . . . . . 183
9.3. Non-standardFeatures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
A Bibliography 187
B Fortran90Overview 191
B.1. ListofLanguageTables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
B.2. AlphabeticalTableofFortran90IntrinsicRoutines . . . . . . . . . . . . . . . . . . . 17
B.3. SyntaxofFortran90Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
C SelectedExerciseSolutions 47
C.1. Problem1.8.1: Checkingtrigonometricidentities . . . . . . . . . . . . . . . . . . . 47
C.2. Problem1.8.2: Newton-Raphsonalgorithm . . . . . . . . . . . . . . . . . . . . . . 47
C.3. Problem1.8.3: Gameoflife . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
C.4. Problem2.5.1: Conversionfactors . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
C.5. Problem3.5.3: Creatingavectorclass . . . . . . . . . . . . . . . . . . . . . . . . . 50
C.6. Problem3.5.4: Creatingasparsevectorclass . . . . . . . . . . . . . . . . . . . . . 56
C.7. Problem4.11.1: Countthelinesinanexternalfile . . . . . . . . . . . . . . . . . . . 61
C.8. Problem4.11.3: ComputingCPUtimeuseage . . . . . . . . . . . . . . . . . . . . . 62
C.9. Problem4.11.4: Convertingastringtouppercase . . . . . . . . . . . . . . . . . . . 62
C.10.Problem4.11.8: Readtwovaluesfromeachlineofanexternalfile . . . . . . . . . . 63
C.11.Problem4.11.14: Twolineleastsquarefits . . . . . . . . . . . . . . . . . . . . . . . 63
C.12.Problem4.11.15: Findthenextavailablefileunit . . . . . . . . . . . . . . . . . . . 65
C.13.Problem5.4.4: Polymorphicinterfacefortheclass‘Position Angle’ . . . . . . . . . 66
C.14.Problem6.4.1: Usingafunctionwiththesamenameintwoclasses . . . . . . . . . . 67
C.15.Problem6.4.3: Revisingtheemployee-managerclasses . . . . . . . . . . . . . . . . 67
D CompanionC++Examples 69
D.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
E GlossaryofObjectOrientedTerms 77
F SubjectIndex 0
G ProgramIndex 1
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vi
Preface
Therehasbeenanexplosionofinterestin,andbooksonobject-orientedprogramming(OOP).Whyhave
yetanotherbookonthesubject? Inthepastabasiceducationwassaidtomasterthethreer’s: reading,
’riting,and’rithmetic.Todayasoundeducationinengineeringprogrammingleadstoproducingcodethat
satisfy the four r’s: readability, reusability, reliability, and really-efficient. While some object-oriented
programming languages have some of these abilities Fortran 90/95 offers all of them for engineering
applications.ThusthisbookisintendedtotakeadifferenttackbyusingtheFortran90/95languageasits
mainOOPtool. With morethanonehundredpureandhybridobject-orientedlanguagesavailable,one
mustbeselectiveindecidingwhichonesmerittheeffortoflearningtoutilizethem. Therearemillions
ofFortranprogrammers,soitislogicaltopresentthehybridobject-orientedfeaturesofFortran90/95to
themtoupdateandexpandtheirprogrammingskills. ThisworkprovidesanintroductiontoFortran90
aswellastoobject-orientedprogrammingconcepts. Evenwiththecurrentrelease(Fortran95)wewill
demonstratethatFortranoffersessentiallyallofthetoolsrecommendedforobject-orientedprogramming
techniques. It is expected that Fortran 200X will offer additional object-oriented capabilities, such as
declaring”extensible” (or virtual) functions. Thus, it is expectedthat the tools learned here will be of
valuefarintothefuture.
Itiscommonlyagreedthatthetwo decadesold F77 standardforthe languagewas missingseveral
usefulandimportantconceptsofcomputersciencethatevolvedandweremadepopularafteritsrelease,
but it also had a large number of powerful and useful features. The following F90 standard included
a large number of improvements that have often been overlooked by many programmers. It is fully
compatiblewithallold F77 standardcode,butitdeclaredseveralfeaturesofthatstandardasobsolete.
Thatwasdonetoencourageprogrammerstolearnbettermethods,eventhoughthestandardstillsupports
thosenowobsoletelanguageconstructs.TheF90standardscommitteebroughtintothelanguagemostof
thebestfeaturesofothermorerecentlanguageslikeAda,C,C++,Eiffel,etc. Thoseadditionsincludedin
part: structures,dynamicmemorymanagement,recursion,pointers(references),andabstractdatatypes
along with their supporting tools of encapsulation, inheritance, and the overloading of operators and
routines.EquallyimportantforthoseinvolvedinnumericalanalysistheF90standardaddedseveralnew
featuresforefficientarrayoperationsthatareverysimilartothoseofthepopularMATLAB environment.
Mostofthosefeaturesincludeadditionaloptionstoemploylogicalfiltersonarrays.Allofthenewarray
featureswereintendedforuseonvectororparallelcomputersandallowprogrammerstoavoidthebad
habitofwritingnumerousserialloops. Thecurrentstandard,F95,wentontoaddmorespecificparallel
arraytools, provided“pure”routinesforgeneralparalleloperations,simplifiedtheuse ofpointers,and
madeafewuserfriendlyrefinementsofsomeF90features. Indeed,atthistimeonecanviewF90/95as
theonlycross-platforminternationalstandardlanguageforparallelcomputing. ThusFortrancontinues
tobeanimportantprogramminglanguagethatrichlyrewardstheeffortoflearningtotakeadvantageof
itspower,clarity,anduserfriendlyness.
We beginthatlearningprocessin Chapter 1 with an overviewof generalprogrammingtechniques.
Primarilytheolder“procedural”approachisdiscussedthere,butthechapterisclosedwithanoutlineof
thenewer“object”approachtoprogramming.Anexperiencedprogrammermaywanttoskipdirectlyto
thelastsectionofChapter1whereweoutlinesomeobject-orientedmethods.InChapter2,weintroduce
theconceptoftheabstractdatatypesandtheirextensiontoclasses. Chapter3providesafairlydetailed
introductiontotheconceptsandterminologyofobject-orientedprogramming.Amuchlargersupporting
glossaryisprovidedasanappendix.
ForthesakeofcompletenessChapter4introduceslanguagespecificdetailsofthetopicsdiscussedin
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thefirstchapter.TheFortran90/95syntaxisusedthere,butinseveralcasescross-referencesaremadeto
similarconstructsintheC++languageandtheMATLABenvironment.Whilesomereadersmaywantto
skipChapter4,itwillhelpotherslearntheFortran90/95syntaxand/ortoreadrelatedpublicationsthat
useC++orMATLAB. AllofthesyntaxofFortran90isalsogiveninanappendix.
Since many Fortran applications relate to manipulating arrays or doing numerical matrix analysis,
Chapter 5 presents a very detailed coverage of the powerfulintrinsic features Fortran 90 has added to
provideformoreefficientoperationswitharrays. Ithasbeendemonstratedintheliteraturethatobject-
orientedimplementationsofscientific projectsrequiringintensiveoperationswith arraysexecutemuch
faster in Fortran 90 than in C++. Since Fortran 90 was designed for operationson vector and parallel
machines that chapter encouragesthe programmerto avoid unneeded serial loops and to replace them
withmoreefficientintrinsicarrayfunctions. Readersnotneedingtousenumericalmatrixanalysismay
skipChapter5.
Chapter6returnstoobject-orientedmethodswithamoredetailedcoverageofusingobject-oriented
analysisandobject-orienteddesigntocreateclassesanddemonstrateshowtoimplementthemasanOOP
in Fortran 90. Additional Fortran 90 examples of inheritance and polymorphismare given in Chapter
7. Object-orientedprogramsoften requirethe objectsto be stored in some type of “container”or data
structure such as a stack or linked-list. Fortran 90 object-oriented examples of typical containers are
giveninChapter8.SomespecializedtopicsformoreadvancedusersaregiveninChapter9,sobeginning
programmerscouldskipit.
Tosummarizethetwooptionalusesofthistext;itisrecommendedthatexperiencedFortranprogram-
merswishingtolearntouseOOPcoverChapters2,3,6,7,8,and9,whilepersonsstudyingFortranfor
thefirsttimeshouldcoverChapters1,2,3,and.Anyoneneedingtousenumericalmatrixanalysisshould
alsoincludeChapter5.
AOOglossaryisincludedinanappendixtoaidinreadingthistextandthecurrentliteratureonOOP.
Another appendix on Fortran 90 gives an alphabetical listing on its intrinsic routines, a subject based
list of them, a detailed syntaxof all the F90 statements, and a set of exampleuses of everystatement.
Selected solutionsfor most of the assignments are included in anotherappendixalong with comments
on those solutions. The final appendix gives the C++ versions of several of the F90 examples in the
text. TheyareprovidedasanaidtounderstandingotherOOPliterature. SinceF90andMATLABareso
similarthecorrespondingMATLABversionsoftendirectlyfollowtheF90examplesinthetext.
EdAkin, RiceUniversity, 2002
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Index
abstractdatatype,15,23,27 rectangular,170
abstraction,19,27 reshape,159
access,36 shape,159
accessrestriction,19 shift,172
accessibility,19 size,159
accessor,18 unknownsize,77
actualargument,56 variablerank,160
Ada,33 arrayoperations,163
addition,56 ASCII,23
ADT,seeabstractdatatype ASCIIcharacterset,77,78,99,163
ADVANCEspecifier,42,103 assemblylanguage,15
agent,18 assignmentoperator,10,39
algorithm,51 ASSOCIATED,15
ALLOCATABLE,15 ASSOCIATEDfunction,76,89
ASSOCIATEDintrinsic,132,134
allocatablearray,160,161
associative,176,177
ALLOCATE,15
asterisk(*),58
allocate,42
ATAN2,13
ALLOCATEstatement,75,93
attribute,105,106,109,121,125
ALLOCATED,15
private,27,125
allocationstatus,75
public,27
ANDoperand,42
terminator,25
area,34
attributeterminator,25
argument
attributes,19,27
inout,71
automaticarray,90,160,161
input,71
automaticdeallocation,29
interface,76
none,71
BACKSPACEstatement,76
numberof,76
badstyle,162
optional,76,77
baseclass,121
order,76
behavior,106,109
output,71
binaryfile,163
rank,76 bit
returnedvalue,76 clear,75
type,76 extract,75
array,26,60,67,83 set,75
allocatable,160 shift,75
assumedshape,77 test,75
automatic,90,160 bitmanipulation,75
Boolean,168 blanks
constant,160 all,78
dummydimension,160 leading,78
flip,170 trailing,78
mask,168,183 Boolean,53
rank,77,159,161,170 Booleanvalue,23
4
bottom-up,4 Drill,106
bounds,159 Global Position,114
bubblesort,93,95 Great Arc,114
ordered,96 Position Angle,114
bug,9 clippingfunction,14,71
CLOSEstatement,75
C,1,33,52 Coad/Yourdonmethod,18
C++,1, 10,14,24,33,52,58,60,77,82,103, colon operator, 56, 61, 62, 78, 160, 163, 167,
123 170
CALLstatement,42 columnmajororder,181
CASEDEFAULTstatement,64 columnmatrix,174
CASEstatement,64 columnorder,162
cases,62 comma,99
centralprocessorunit,73 comment,1,2,7,9,12,52
character,82 commutative,101,176,177
casechange,81 compiler,10,15,91
control,77 complex,10,82,165
fromnumber,81 COMPLEXtype,23,53
functions,78 COMPLEXtype,24
non-print,103 composition,34,36
non-printable,77 conditional,7–9,11,51,58
strings,77 conformable,176
tonumber,81 connectivity,170
characterset,23 constantarray,160
CHARACTERtype,23,26,53 constructor,18,29,34,125,134,135
chemicalelement,25 default,18
circuits,170 intrinsic,18,26,34,39
circularshift,172 manual,36
class,15,19,33 public,37
base,18 structure,26
Date,120,123 CONTAINSstatement,29,33,34,73,76,86
derived,18 continuationmarker,10
Drill,105 controlkey,79
Employee,125 conversionfactors,29
Geometric,120 count-controlledDO,12,13
Global Position,114 CPU,seecentralprocessorunit
Great Arc,114 curvefit,91
hierarchy,33 CYCLEstatement,66
instance,33
Manager,125,135 dataabstraction,19
Person,120,123 datahiding,36
polymorphic,133 datatypes,10
Position Angle,109,114 intrinsic,23
Professor,123 userdefined,23
Student,120,123 date,101
classcode DEALLOCATE,15
class Angle,114 deallocate,18,42
class Circle,34 DEALLOCATEstatement,75
class Date,37 debugger,17
class Fibonacci Number,29 debugging,16
class Person,37 defaultcase,64
class Rational,42 defaultvalue,29
class Rectangle,34 dereference,58
class Student,37 derivedclass,121
c2002 J.E. Akin 5
(cid:13)