Python Programming: An Introduction to Computer Science

PythonProgramming: AnIntroductiontoComputerScience JohnM.Zelle,Ph.D. Version1.0rc Fall 2002 ...

Copyrightc 2002 byJohnM.Zelle Allrightsreserved.Nopartofthispublicationmaybereproduced,storedin a retrieval system,ortransmitte ...

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1 ComputersandPrograms 1.1 TheUniversalMachine. 1.2 ProgramPower 1.3 Whatis ComputerScience?. 1.4 HardwareBasics 1.5 Programmin ...

vi CONTENTS ...

Chapter 1 Computers and Programs Almosteveryonehasuseda computeratonetimeoranother. Perhapsyouhave playedcomputergamesor useda c ...

2 CHAPTER1. COMPUTERSANDPROGRAMS 1.2 ProgramPower Youhave alreadylearnedanimportantlessonofcomputing:Software(programs)rulestheh ...

1.4.HARDWAREBASICS 3 Input Devices CPU Secondary Memory Main Memory Output Devices Figure1.1:FunctionalView ofa Computer. analys ...

4 CHAPTER1. COMPUTERSANDPROGRAMS 1.5 ProgrammingLanguages Rememberthata programis justa sequenceofinstructionstellinga computerw ...

1.6.THEMAGICOFPYTHON 5 (Program) Compiler Machine Code Running Inputs Outputs Source Code Program Figure1.2:Compilinga High-Leve ...

6 CHAPTER1. COMPUTERSANDPROGRAMS print "Hello, World" Hello, World print 2 + 3 5 print "2 + 3 =", 2 + 3 2 + 3 = 5 HereI ha ...

1.6.THEMAGICOFPYTHON 7 Canyouseewhatis happeninghere?Whenweusegreetwecansenddifferentnamestocustomizethe result.We willdiscusspa ...

8 CHAPTER1. COMPUTERSANDPROGRAMS Typingthefirstlineimport chaostellsthePythoninterpretertoloadthechaosmodulefromthefile chaos.py ...

1.7.INSIDEA PYTHONPROGRAM 9 File: chaos.py A simple programillustrating chaotic behavior. print "This programillustrates a chaot ...

10 CHAPTER1. COMPUTERSANDPROGRAMS print x x = 3.9 x (1 - x) print x Obviouslyusingtheloopinsteadsavestheprogrammera lotoftroub ...

1.9.EXERCISES 11 0.166187 0. 0.540418 0. 0.968629 0. 0.118509 0. Withverysimilarstartingvalues,theoutputsstaysimilarfora fewiter ...

12 CHAPTER1. COMPUTERSANDPROGRAMS x = 2.0 * x * (1 - x) Runtheprogramforvariousinputvaluesandcomparetheresultstothoseobtainedfro ...