Welcome'to'BBM'101' Course'Introduc-on' Course'Staff' Course'Staff' Lecturers:# TAs#(teaching#assistants):# # # Do#not#hesitate#to#ask#TAs#for#help!

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1 Welcome'to'BBM'101' Course'Introduc-on' BBM101&Introduc/ontoProgrammingI Hace7epeUniversity Fall2015 FuatAkal,AykutErdem,ErkutErdem,VahidGarousi Thiscourseteachescoreprogrammingconceptswith anemphasisondatamanipula/ontasksfrom science,engineering,andbusiness Goalbytheendofthesemester:Givenadata sourceandaproblemdescrip/on,youcan independentlywriteacomplete,usefulprogramto solvetheproblem SlidesbasedonmaterialpreparedbyRuthAnderson,MichaelErnstandBillHoweinthecourseCSE140 UniversityofWashington 1 2 Course'Staff' Course'Staff' Lecturers: Asst.Prof.Dr.FuatAkal Asst.Prof.Dr.AykutErdem Asst.Prof.Dr.ErkutErdem Assoc.Prof.Dr.VahidGarousi 3 TAs(teachingassistants): BurçakAsal FeyzaNurÇubukçuoğlu LeventKaracan SelimYılmaz DonothesitatetoaskTAsforhelp! 4

2 Learning'Objec-ves' What'This'Course'is'not' Computa/onalproblem&solving A skillscourse inpython BasicPythonproficiency Adataanalysis/ datascience /datavisualiza/oncourse thoughyouwillbecomeproficientinthebasicsofthepython programminglanguage andyouwillgainexperiencewithsomeimportantpythonlibraries Wri/ngaprogramwillbecomeyour go&to solu/on fordataanalysistasks. Therewillbeveryli7lesta/s/csknowledgeassumedortaught Includingexperiencewithrelevantlibrariesfordata manipula/on,scien/ficcompu/ng,andvisualiza/on. A project course theassignmentsare real, butareintendedtoteachspecific programmingconcepts Experienceworkingwithrealdatasets astronomy,biology,linguis/cs,oceanography,open government,socialnetworks,andmore. Youwillseethattheseareeasytoprocesswitha program,andthatdoingsoyieldsinsight. A sohwareengineering course Programmingisthestar/ngpointofcomputerscienceandsohware engineering 5 6 All'of'Science'is'Reducing'to' Computa-onal'Data'Manipula-on'! It s!a!great!+me!to!be!a!data!geek.!!!!!old!model:! Query!the!world!!(Data!acquisi7on!coupled!to!a!specific!hypothesis)!!!!!New!model:! Download!the!world!(Data!acquisi7on!supports!many!hypotheses) Astronomy:'HighIresolu-on,'highIfrequency'sky'surveys'(SDSS,'LSST,'PanSTARRS)' Biology:'lab'automa-on,'highIthroughput'sequencing,'' Oceanography:'highIresolu-on'models,'cheap'sensors,'satellites 33!Roger!Barga,!Microso:!Research!!! The!greatest!minds!of!my!genera+on!are!trying!! to!figure!out!how!to!make!people!click!on!ads! 40TB/2nights 33!Jeff!Hammerbacher,!co3founder,!Cloudera!! ~1TB/day 100sofdevices 7 8

3 Example:'Assessing'Treatment' Efficacy' Python'Program'to'Assess'Treatment'Efficacy' numberoffollowups within16weeksaher treatmentenrollment. Zipcodeofclinic Ques+on:!Does!the!distance!between!the! pa+ent s!home!and!clinic!influence!the!number! of!follow!ups,!and!therefore!treatment!efficacy?! Zipcodeofpa/ent 9 ThisprogramreadsanExcelspreadsheetwhosepenul/mate andantepenul/matecolumnsarezipcodes. Itaddsanewlastcolumnforthedistancebetweenthosezip codes,andoutputsincsv(comma&separatedvalues)format. Calltheprogramwithtwonumericvalues:thefirstandlast rowtoinclude. Theoutputcontainsthecolumnheadersandthoserows. Librariestouse importrandom importsys importxlrdlibraryforworkingwithexcelspreadsheets import/me fromgdapiimportgoogledirec/ons Nokeyneedediffewqueries gd=googledirec/ons('dummy&google&key') wb=xlrd.open_workbook('mhip_zip_escience_121611a.xls') sheet=wb.sheet_by_index(0) Userinput:firstrowtoprocess,firstrownottoprocess first_row=max(int(sys.argv[1]),2) row_limit=min(int(sys.argv[2]+1),sheet.nrows) defcomma_separated(lst): return,.join([str(s)forsinlst]) headers=sheet.row_values(0)+[distance] printcomma_separated(headers) forrownuminrange(first_row,row_limit): row=sheet.row_values(rownum) (zip1,zip2)=row[&3:&1] ifzip1andzip2: Cleanthedata zip1=str(int(zip1)) zip2=str(int(zip2)) row[&3:&1]=[zip1,zip2] ComputethedistanceviaGoogleMaps try: distance=gd.query(zip1,zip2).distance except: print>>sys.stderr,errorcompu/ngdistance:,zip1,zip2 distance= Printtherowwiththedistance printcomma_separated(row+[distance]) AvoidtoomanyGooglequeriesinrapidsuccession /me.sleep(random.random()+0.5) 23linesofexecutablecode! 10 Course'Logis-cs' Academic'Integrity' Website: Seethewebsiteforalladministra/vedetails Readthehandoutsandrequiredtexts,beforethelecture Takenotes! FollowthecourseinPiazza fall2015/bbm101 Honestworkisrequiredofascien/storengineer. Collabora/onpolicyonthecourseweb.Read'it!' Discussionispermi7ed. Carrying'materials'from'discussion'is'not'permiTed.' Everythingyouturninmustbeyourownwork. Citeyoursources,explainanyunconven/onalac/on. You'may'not'view'others 'work.' Ifyouhaveaques/on,ask. Wetrustyoucompletely. Butwehavenosympathyfortrustviola/ons norshouldyou! 11 12

4 How'to'Succeed' Integrated'Development'Environment'(IDE)' Noprerequisites Non&predictorsforsuccess: Pastprogrammingexperience Enthusiasmforgamesorcomputers Programminganddataanalysisarechallenging Everyoneofyoucansucceed Thereisnosuchthingasa bornprogrammer Workhard Followdirec/ons Bemethodical Thinkbeforeyouact Tryonyourown,thenaskforhelp Startearly 13 Therearemany! 14 Our'Recommenda-on:'PyCharm' Python'Version' WhateverIDEyouchoosetoworkwith, alwayss/cktopython'version'2.7.10' ' Alwaysusethisversiontocodeyour assignments

5 Books' Therearemany! Our'Recommenda-on'for'Books' ThePythonTutorial,availablefromthePythonwebsite. ThisisgoodforexplainingthenutsandboltsofhowPythonworks. ThinkPython,2ndedi/on FreelyavailableonlineinHTMLandPDF. Alsoavailableforpurchaseasaprintedbook,butdon'tbuythefirst edi/on. Thisbookintroducesmoreconceptualmaterial,mo/va/ng computa/onalthinking. Thereisan interac/veversionof HowtoThinkLikeaComputerScien/st (the firstedi/onof ThinkPython ),whichletsyoutypeandrunpython codedirectlywhilereadingthebook

6 1.Pythonisacalculator 2.Avariableisacontainer Introduc)on*to*Python* and*programming* BBM101EIntroducGontoProgrammingI HaceIepeUniversity Fall2015 FuatAkal,AykutErdem,ErkutErdem,VahidGarousi 3.Differenttypescannotbecompared 4.Aprogramisarecipe SlidesbasedonmaterialpreparedbyRuthAnderson,MichaelErnstandBillHoweinthecourseCSE140 UniversityofWashington *Python*is*Like*a*Calculator* You*Type*Expressions.* Python*Computes*Their*Values.* /2 2**3 3*4+5*6 Ifprecedenceisunclear,useparentheses (72 32)/9*5 3 4

7 An*Expression*is*Evaluated* From*the*Inside*Out* HowmanyexpressionsareinthisPythoncode? anexpression (72 32)/9.0*5 values (72 32)/9.0*5* (40)/9.0*5* 40/9.0*5* 4.44*5* 22.2* Another*Evalua)on*Example* (72 32)/(9.0*5)* (40)/(9.0*5)* 40/(9.0*5)* 40/(45.0)* 40/45.0*.888* *A*Variable*is*a*Container* Variables*Hold*Values* Recallvariablesfromalgebra: Letx=2 Lety=x Toassignavariable,use varname=expression pi = 3.14 pi var = 6*10**23 22 = x Error! Nooutputfroman assignmentstatement 7 NotallvariablenamesarepermiIed 8

8 Changing*Exis)ng*Variables* ( repbinding *or* repassigning )* x = 2 x y = 2 x y x = 5 x Y = inanassignmentisnotapromiseofeternalequality ThisisdifferentthanthemathemaGcalmeaningof = EvaluaGnganexpressiongivesanew(copyofa)number, ratherthanchanginganexisgngone 9 How*an*Assignment*is*Executed* 1. EvaluatetherightEhandsidetoavalue 2. Storethatvalueinthevariable x = 2 print(x) y = x print(y) z = x + 1 print(z) x = 5 print(x) print(y) print(z) Stateofthecomputer: x:2 x:5 y:2 z:3 Printedoutput: Tovisualizeaprogram sexecugon: hip://pythontutor.com 10 More*Expressions:**Condi)onals* (value*is*true*or*false)* More*Expressions:**strings* 22 > 4 condigon,orcondigonal 22 < 4 condigon,orcondigonal 22 == 4 x == 100 Assignment,notcondiGonal! 22 = 4 Error! x >= 5 x >= 100 Numericoperators:+,*,** Booleanoperators:not,and,or Mixedoperators:<,>=,== x >= 200 not True not (x >= 200) 3<4 and 5<6 4<3 or 5<6 temp = 72 water_is_liquid = (temp > 32 and temp < 212) 11 A*string*represents*text* 'Python' mystring = BBM 101-Introduction to Programming Empty*string*is*not*the*same*as*an*unbound*variable* *and* *are*the*same* Opera)ons:* Length:* len(mystring) Concatena)on:* Hacettepe + + ' University' Containment/searching:* a' in mystring a in mystring 12

9 3.*Different*Types*cannot*be*Compared* Types*of*Values* anint = 2 astring = Hacettepe anint == astring Error Integers(int):-22,0,44 ArithmeGcisexact SomefunnyrepresentaGons: L * Realnumbers(float,for floagngpoint ):2.718, ArithmeGcisapproximate,e.g.,6.022*10**23 SomefunnyrepresentaGons:6.022e+23 Strings(str):I love Python, Truthvalues(bool,for Boolean ): True,False 13 GeorgeBoole 14 Opera)ons*Behave*differently* on*different*types* ConcatenaGon Error 3 + True Error Moral:Pythononlysome-mestellsyouwhenyou dosomethingthatdoesnotmakesense. Opera)ons*on*Different*Types* 15.0 / / / 4 15 / 4.0 Typeconversion: float(15) int(15.0) int(15.5) int(15) str(15.5) float(15) /

10 A*Program*is*a*Recipe* Design*the*Algorithm*Before*Coding* Weshouldthink(designthealgorithm)beforecoding Algorithmicthinkingisthelogic.Also,calledproblem solving Codingisthesyntax Makethisahabit SomestudentsdonotfollowthispracGceandtheyget challengedinalltheircoursesandcareers! What*is*a*Program?* The**print()*Statement* AprogramisasequenceofinstrucGons Thecomputerexecutesoneanertheother,asiftheyhadbeen typedtotheinterpreter SavingyourworkasaprogramisbeIerthanreEtypingfrom scratch x = 1 y = 2 x + y print(x + y) print(the sum of, x, and, y, is, x+y) 19 Theprintstatementalwaysprintsoneline Thenextprintstatementprintsbelowthatone Write0ormoreexpressionsanerprint,separatedby commas Intheoutput,thevaluesareseparatedbyspaces Examples: x=1 y=2 print(3.1415) print(2.718, 1.618) Print() print(20 + 2, 7 * 3, 4 * 5) print(the sum of, x, and, y, is, x+y) 20

11 Exercise:**Convert*Temperatures* Expressions,*Statements,*and*Programs* Makeatemperatureconversionchartasthefollowing FahrenheittoCenGgrade,forFahrenheitvaluesof:E40,0,32,68,98.6, 212 C=(FE32) 5/9 Output: Fahrenheit Centigrade YouhavecreatedaPythonprogram! (Itdoesn thavetobethistedious,anditwon tbe.) 21 Anexpressionevaluatestoavalue pi * r**2 Astatementcausesaneffect pi = print(pi) Expressionsappearwithinotherexpressionsandwithinstatements (fahr 32) * (5.0 / 9) print(pi * r**2) Astatementmaynotappearwithinanexpression 3 + print(pi) *Error!* * Aprogramismadeupofstatements AprogramshoulddosomethingorcommunicateinformaGon 22 print()*func)on* 1.Pythonisacalculator 2.Avariableisacontainer 3.Differenttypescannotbecompared 4.Aprogramisarecipe 23 24

12 Programming*Languages* Evolu)on*of*Programming*Languages* Aprogramminglanguageisa language towriteprograms in,suchaspython,c,c++,java Theconceptofprogramminglanguagesarequitesimilar Python: Java: Pythonissimpler!That swhywearelearningitfirst! hip://blog.codeeval.com/codeevalblog/