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Government of Tamil Nadu,First Edition 2019,Published under New Syllabus. NOT FOR SALE,Content Creation,possess all,State Council of Educational. Research and Training,SCERT 2019,Printing Publishing. Tamil NaduTextbook and Educational,Services Corporation. www textbooksonline tn nic in,Index indd 2 20 02 2019 15 06 40.
The tremendous e ect of the computer and computing technology is in. shaping the modern society for the betterment of mankind Human. civilization achieved the highest peak with the development. of computer known as Internet Era, PREFACE Python being a high level language is good. for beginners to learn due to its easy syntax,and powerful memory management For any. internet applications it is good to learn as python being the. better choice, The user of this textbook being acquainted with the knowledge of C in. std XI will have no di culty in studying python language No substantial. knowledge nor experience is required as the examples illustrated in the. book are easy to follow,This book does not require TO USE. prior knowledge in computer,Technology,Each unit comprises of simple.
activities and demonstrations which can be done by. the teacher,and also students, Technical terminologies are listed in glossary for easy understanding. The Do you know boxes enrich the knowledge of reader with. additional information, Workshops are introduced to solve the exercises using software. applications,QR codes are used to link supporting additional. materials in digital form,How to get connected to QR Code. o Download the QR code scanner from the google play store. apple app store into your smartphone,o Open the QR code scanner application.
o Once the scanner button in the application is clicked camera opens. and then bring it closer to the QR code in the textbook. o Once the camera detects the QR code a URL appears in the screen. Click the URL and go to the content page,Index indd 3 20 02 2019 15 06 40. Index indd 4,Computer Knowledge Hub PG in Computer Science. Centre for Development of Advanced Computing https www cdac in Artificial Intelligence Database Management. Indian Computing Olympiad https www iarcs org in inoi Information Management Systems. International Olympiad of Informatics https ioinformatics org and Data Analytics Fundamentals of Algorithms. Microsoft certification exams https www microsoft com en in learning exam list aspx Algorithms Graphics. National Cyber Olympiad http www sofworld org nco Applied Computer Science Machine Learning. Big Data Analytics Mobile and Web Computing, National Institute of Electronics Information Technology http www nielit gov in. Bio Informatics Mobile Device Programming, National Programme on Technology Enhanced Learning https nptel ac in. Cloud Computing Modern Programming Practices,Compiler Design Modern Web Applications.
Construction Operating Systems, After Completing 2 Computer and Network Parallel Programming. Security Robotics,Arts Science BSc Courses Animation Multimedia. Computer Networks Software Engineering,Computer Science Geography. Computer Security Software Engineering, Journalism Mass Media Communication Library Science. Computer Simulation Software Testing, Maths Physics Chemistry Statistics Psychology Sociology.
Cyber Security Systems Analysis and Design, Social Work Visual Communication B C A COMPUTER Data Analytics Web Application Architecture. SCIENCE Data Mining Web Application Programming,Technical Diploma. Scholarships for graduate,Diploma in Engineering and post graduate courses. DST INSPIRE Fellowships for Ph D, Professional Degree Entrance Exams DST INSPIRE Scholarships. for UG and PG, Hotel Catering Institute http www ihmchennai org ihmchennai JEE Joint Entrance Examination https jeemain nic in In addition various fellowships for.
AIEEE All India Engineering Entrance Exam JEST Joint Entrance Screening Test https www jest org in SC ST PWD. B E B Tech B Arch JEE AIEEE in IITs and NITs Law 5 Year Integrated Course http tndalu ac in Indira Gandhi Fellowship for. Fashion Technology Design http nift ac in National Defence Academy https www nda nic in Single girl child for UG and PG. GATE Graduate Aptitude Test in Engineering NET National Eligibility Test CSIR and UGC http cbsenet nic in Moulana Azad Fellowship. www gate iitm ac in TamilNadu Dr Ambedkar Law University http tndalu ac in for minorities for Ph D. Indian Navy 10 2 BTech Entry Scheme Technical Entry Scheme Army Navy Airforce UGC National Fellowship for Ph D. Institute of Chartered Accountants of India https icai org TIFR GS Tata Institute of Fundamental. CAREER GUIDANCE AFTER 12TH,International Olympiad for getting stipend for. Institute of Company Secretary https www icsi edu Research Graduate School http univ tifr res in Higher Education in Science and Mathematics. Institute of Cost Accountants of India http icmai in Visual Arts Degree OBC etc are available. Institute of Banking Personal Selection IBPS https ibps in http www tndipr gov in television traininginstitute aspx. Visit website of University Grants Commission,20 02 2019 15 06 40. Index indd 5,After PG courses,A Competitive Exams for Govt Jobs. MPhil Computer Science PhD Computer Science Airforce Common Admission Test AFCAT Army Education Officer Entry AEC. Combined Defence Services CDS Defence Service Staff College Nilgiris. Following are the latest topics for PhD in computer science. Indian Defence Services Indian Military Academy,BioInformatics and Computational Biology. Judge Advocate General Department JAG NCC Entry Railway Board Examination. Capturing and Visualizing Persona Through Faces, SSC NAVY Pilot Observer SSC Tech Entry Officers Training School.
Comprehensive analysis of RNA sequencing experiments Staff Selection Examination Tamil Nadu Public Service Commission. Designing and Evaluating Information Gathering Robots Teacher Recruitment Board Technical Graduate Course TGC. Digital Pathology Diagnostic Errors Territorial Army Union Public Service Examination Women Special Entry Scheme. Viewing Behavior and Image Characteristics,Embedded Systems Game Theory Graph Theory. Graphics and Visualization Human Computer Interaction HCI Computer Related Jobs. Improving Fault Tolerance and Performance of Data Center Networks. Increasing Access to Computer Science for Blind Students Applications Software Developer Big Data Analysts. In situ Semantic 3D Modeling Cloud Computing Programmer College University Faculty. Intelligent Crowdsourcing for Natural Language Computer Programmer Computer Teacher. Learning and Other AI Applications Computer Vocational Instructor Computer Information Research Scientist. Learning Robust Tractable Models for Vision COMPUTER Computer Information Systems Manager Computer Network Architect. SCIENCE Computer Support Specialist Computer System Analysts. Manipulators And Manipulation In High Dimensional Spaces. Data Mining Specialist Database Administrator, New Algorithmic Tools for Distributed Similarity Search. Information Security Analysts Market Research Analysts. Reproducible measurements of web security and privacy Network Computer System Administrator Research Assistant. The Security and Privacy of Web and Mobile Advertising Systems Software Developer User Interface Designer Web Developer. Towards More Practical Reinforcement Learning,with Applications to Educational Games. Research Institutions in various areas of science, Bhaba Atomic Research centre Institute of Mathematical Sciences IMSc. BARC Mumbai www barc gov in Chennai www imsc res in. CAREER GUIDANCE, BITS Pilani https www bits pilani ac in Jawaharlal Nehru University JNU www jnu ac in.
Topics for Research after PG in Computer Studies, Central Universities www ugc ac in Mumbai University Mumbai www mu ac in. Chennai Mathematical Institute National Institute of Science Education and. Architectures Compiler Optimization and Embedded Systems CMI Chennai www cmi ac in Research NISER www niser ac in. Bioinformatics and Computational Biology Cloud Computing Delhi University Delhi www du ac in National Institute of Technology. Hyderabad central university NITs www nitt edu, Data Mining Databases and Geographical Information Systems. Hyderabad www uohyd ac in SavithiribaiPhule Pune university. Graphics and Visualization High Performance Computing Pune www unipune ac in. IISER Educational Institutions, Human Computer Interaction Internet of Things www iiseradmission in State Universities https www ugc ac in. Natural Language Processing Networks Distributed Systems and Security Indian Institute of Technology in Tata Institute of Fundamental Research. various places IIT s www iitm ac in TIFR Mumbai www tifr res in. 20 02 2019 15 06 41,Table of Contents,Computer Science II Year. UNIT No Chapter Title,UNIT I 1 Function 1,Problem 2 Data Abstraction 11.
Solving 3 Scoping 21,Techniques 4 Algorithmic Strategies 31. 5 Python Variables and Operators 47,UNIT II 6 Control Structures 67. Core Python 7 Python functions 89,8 Strings and String manipulations 114. UNIT III 9 Lists Tuples Sets and Dictionary 132,Modularity. and OOPS 10 Python Classes and objects 170,UNIT IV 11 Database Concepts 189.
12 Structured Query Language SQL 205,concepts and,MySql 13 Python and CSV files 232. UNIT V 14 Importing C programs in Python 267,Integrating 15 Data manipulation through SQL 291. Python with Data visualization using pyplot line chart pie. MySql and C 16 320,chart and bar chart,Glossary 335. Annexure 1 List of Python functions 341, Annexure 2 Installation of MySQL and Creating a Database 345. Annexure 3 Installation of MinGW 346,Annexure 4 Installation of pip 351.
E book Assessment DIGI links,Index indd 6 20 02 2019 15 06 41. 1 2 Function with respect to,Learning Objectives Programming language. After the completion of this chapter the A function is a unit of code that is. student will be able to often defined within a greater code structure. Specifically a function contains a set of,Understand Function Specification. code that works on many kinds of inputs, Parameters and arguments like variants expressions and produces a. Interface Vs Implementation concrete output,Pure functions 1 2 1 Function Specification.
Side effects impure functions Let us consider the example a 24. a 24 has an expression in it but 24, 1 1 Introduction is not itself an expression Rather it is a. The most important criteria in function definition Definitions bind values. writing and evaluating the algorithm is the to names in this case the value 24 being. time it takes to complete a task To have bound to the name a Definitions are not. a meaningful comparison of algorithms expressions at the same time expressions are. the duration of computation time must be also not treated as definitions Definitions. independent of the programming language are distinct syntactic blocks Definitions can. compiler and computer used As you have expressions nested inside them and. aware that algorithms are expressed using vice versa. statements of a programming language If a 1 2 2 Parameters and arguments. bulk of statements to be repeated for many, numbers of times then subroutines are used Parameters are the variables in a. to finish the task function definition and arguments are. the values which are passed to a function,Subroutines are the basic building definition. blocks of computer programs Subroutines,1 Parameter without Type. are small sections of code that are used to, perform a particular task that can be used Let us see an example of a function.
repeatedly In Programming languages these definition. subroutines are called as Functions,Chapter 1 indd 1 20 02 2019 15 17 15. mandatory Generally we can leave out, requires b 0 these annotations because it s simpler to. returns a to the power of b let the compiler infer them There are times. let rec pow a b we may want to explicitly write down types. if b 0 then 1 This is useful on times when you get a type. else a pow a b 1 error from the compiler that doesn t make. sense Explicitly annotating the types can,help with debugging such an error message. In the above function definition,variable b is the parameter and the value. The syntax to define functions is close,which is passed to the variable b is the.
to the mathematical usage the definition is,argument The precondition requires and. introduced by the keyword let followed by,postcondition returns of the function. the name of the function and its arguments,is given Note we have not mentioned any. then the formula that computes the image,types data types Some language compiler. of the argument is written after an sign If,solves this type data type inference.
you want to define a recursive function use,problem algorithmically but some require. let rec instead of let,the type to be mentioned,Syntax The syntax for function definitions. In the above function definition if,expression can return 1 in the then branch. by the typing rule the entire if expression let rec fna1 a2 an k. has type int Since the if expression has, type int the function s return type also be Here the fn is a variable indicating. int b is compared to 0 with the equality an identifier being used as a function. operator so b is also a type of int Since a name The names a1 to an are variables. is multiplied with another expression using indicating the identifiers used as parameters. the operator a must be an int The keyword rec is required if fn is to be. a recursive function otherwise it may be,2 Parameter with Type.
Now let us write the same function,definition with types for some reason. requires b 0 A function definition which call,itself is called recursive function. returns a to the power of b,let rec pow a int b int int. For example let us see an example to check,if b 0 then 1. whether the entered number is even or odd,else a pow b a 1.
When we write the type annotations,for a and b the parentheses are. XII Std Computer Science 2,Chapter 1 indd 2 20 02 2019 15 17 15. interface In our example anything that,requires x 0. let rec even x ACTS LIKE a light should have function. x 0 odd x 1 definitions like turn on and a turn off. return even The purpose of interfaces is to allow the. requires x 0 computer to enforce the properties of the. let odd x class of TYPE T whatever the interface is. x 0 even x 1 must have functions called X Y Z etc,return odd. A class declaration combines the, The syntax for function types external interface its local state with an.
implementation of that interface the code,x y that carries out the behaviour An object is. x1 x2 y an instance created from the class,The interface defines an object s visibility to. the outside world,The x and y are variables indicating. types The type x y is the type of a function The difference between interface and. that gets an input of type x and returns an implementation is. output of type y Whereas x1 x2 y is, a type of a function that takes two inputs Interface Implementation. the first input is of type x1 and the second, input of type x2 and returns an output of Interface just Implementation.
type y Likewise x1 xn y has defines what carries out the. type x as input of n arguments and y type an object can instructions defined. do but won t in the interface,actually do it,Note In object oriented programs classes are. All functions are static the interface and how the object is processed. definitions There is no dynamic and executed is the implementation. function definitions,1 3 1 Characteristics of interface. The class template specifies the interfaces,1 3 Interface Vs Implementation. to enable an object to be created and, An interface is a set of action that an operated properly. object can do For example when you press, a light switch the light goes on you may An object s attributes and behaviour is.
not have cared how it splashed the light In controlled by sending functions to the. Object Oriented Programming language object,an Interface is a description of all functions. that a class must have in order to be a new For example let s take the example of. increasing a car s speed,3 Function,Chapter 1 indd 3 20 02 2019 15 17 15. let min 3 x y z,ENGINE if x y then,if x z then x else z. if y z then y else z,1 4 Pure functions,required No Pure functions are functions which. speed will give exact result when the same,arguments are passed For example the.
mathematical function sin 0 always results,Return 0 This means that every time you call the. function with the same arguments you will,always get the same result A function can. The person who drives the car be a pure function provided it should not. doesn t care about the internal working To have any external variable which will alter. increase the speed of the car he just presses the behaviour of that variable. the accelerator to get the desired behaviour, Here the accelerator is the interface between Let us see an example. the driver the calling invoking object and,the engine the called object let square x. In this case the function call would return x x,be Speed 70 This is the interface.
Internally the engine of the car is The above function square is a pure. doing all the things It s where fuel air function because it will not give different. pressure and electricity come together to results for same input. create the power to move the vehicle All of,There are various theoretical. these actions are separated from the driver,advantages of having pure functions One. who just wants to go faster Thus we separate,advantage is that if a function is pure then. interface from implementation,if it is called several times with the same. Let us see a simple example consider arguments the compiler only needs to. the following implementation of a function actually call the function once Lt s see an. that finds the minimum of its three example,if i strlen s then.
Do something which doesn t affect s,XII Std Computer Science 4. Chapter 1 indd 4 20 02 2019 15 17 15, If it is compiled strlen s is called Here the function Random is impure. each time and strlen needs to iterate over as it is not sure what will be the result when. the whole of s If the compiler is smart we call the function. enough to work out that strlen is a pure,1 4 2 Side effects Impure functions. function and that s is not updated in the, loop then it can remove the redundant As you are aware function has side. extra calls to strlen and make the loop to effects when it has observable interaction. execute only one time From these what we with the outside world There are situations. can understand strlen is a pure function our functions can become impure though. because the function takes one variable as a our goal is to make our functions pure. parameter and accesses it to find its length Just to clarify remember that side effect is. This function reads external memory but not a necessary bad thing Sometimes they. does not change it and the value returned are useful especially outside functional. derives from the external memory accessed programming paradigm. Modify variable outside a function,Note One of the most popular groups of.
Evaluation of pure side effects is modifying the variable outside. functions does not cause any side of function,effects to its output. For example,1 4 1 Impure functions,int inc int x,The variables used inside the. function may cause side effects though the,functions which are not passed with any. arguments In such cases the function is,In the above example the value of y. called impure function When a function,get changed inside the function definition.
depends on variables or functions outside,due to which the result will change each. of its definition block you can never be,time The side effect of the inc function is. sure that the function will behave the same,it is changing the data of the external visible. every time it s called For example the,variable y As you can see some side effects. mathematical function random will give,are quite easy to spot and some of them may.
different outputs for the same function call,tricky A good sign that our function impure. let Random number has side effect is that it doesn t take any. arguments and it doesn t return any value,let a random. if a 10 then From all these examples and,return a definitions what we can understand about. else the main differences between pure and,return 10 impure functions are. 5 Function,Chapter 1 indd 5 20 02 2019 15 17 15,1 4 3 Chameleons of Chromeland.
Pure Function Impure Function,problem using function. The return value of The return value Recall the In the Chameleons of. the pure functions of the impure Chromeland problem what you have studied. solely depends functions does in class XI suppose two types of chameleons. on its arguments not solely depend,are equal in number Construct an algorithm. passed Hence if on its arguments, you call the pure passed Hence that arranges meetings between these two. functions with if you call the types so that they change their color to the. the same set of impure functions third type In the end all should display the. arguments you with the same same color,will always get set of argu ments. the same return you might get Let us represent the number of. values the different chameleons of each type by variables a b. return values and c and their initial values by A B and C. They do not have For example respectively Let a b be the input property. any side effects random Date,The input output relation is a.
They do not They may modify,b 0 and c A B C Let us name the. modify the the arguments, arguments which which are passed algorithm monochromatize The algorithm. are passed to them to them can be specified as,monochromatize a b c. Now let s see the example of a pure,function to determine the greatest common. inputs a A b B c C a b,divisor gcd of two positive integer numbers.
outputs a b 0 c A B C,let rec gcd a b, if b 0 then gcd b a mod b else return a In each iterative step two chameleons. output of the two types equal in number meet and, gcd 13 27 change their colors to the third one For. int 1 example if A B C 4 4 6 then the series,gcd 20536 7826 of meeting will result in. iteration a b c,In the above example program gcd is. the name of the function which recursively 0 4 4 4. called till the variable b becomes 0,Remember b and a mod b are two.
arguments passed to a and b of the gcd 2 2 2 10,XII Std Computer Science 6. Chapter 1 indd 6 20 02 2019 15 17 15,In each meeting a and b each. decreases by 1 and c increases by 2 The,a b a A b B c C. solution can be expressed as an iterative,a 0 a b c a 1 b 1 c 2. monochromatize a b c,inputs a A b B c C a b False,a b 0 c A B C.
outputs a b 0 c A B C,a b c a 1 b 1 c 2,Now let us write this algorithm using. The algorithm is depicted in the flowchart,as below let rec monochromatize a b c. if a 0 then,a b c a 1 b 1 c 2,a 0 b 0 c a b c,Points to remember. Algorithms are expressed using statements of a programming language. Subroutines are small sections of code that are used to perform a particular task that. can be used repeatedly, A function is a unit of code that is often defined within a greater code structure. A function contains a set of code that works on many kinds of inputs and produces a. concrete output,Definitions are distinct syntactic blocks.
Parameters are the variables in a function definition and arguments are the values. which are passed to a function definition through the function definition. When you write the type annotations the parentheses are mandatory in the function. definition, An interface is a set of action that an object can do. Interface just defines what an object can do but won t actually do it. Implementation carries out the instructions defined in the interface. Pure functions are functions which will give exact result when the same arguments. are passed, The variables used inside the function may cause side effects though the functions. which are not passed with any arguments In such cases the function is called impure. 7 Function,Chapter 1 indd 7 20 02 2019 15 17 15,Hands on Practice. 1 Write algorithmic function definition to find the minimum among 3 numbers. 2 Write algorithmic recursive function definition to find the sum of n natural numbers. Evaluation,Choose the best answer 1 Mark, 1 The small sections of code that are used to perform a particular task is called. A Subroutines B Files C Pseudo code D Modules, 2 Which of the following is a unit of code that is often defined within a greater code.
A Subroutines B Function C Files D Modules, 3 Which of the following is a distinct syntactic block. A Subroutines B Function C Definition D Modules, 4 The variables in a function definition are called as. A Subroutines B Function C Definition D Parameters. 5 The values which are passed to a function definition are called. A Arguments B Subroutines C Function D Definition, 6 Which of the following are mandatory to write the type annotations in the function. definition, A Curly braces B Parentheses C Square brackets D indentations. 7 Which of the following defines what an object can do. A Operating System B Compiler C Interface D Interpreter. 8 Which of the following carries out the instructions defined in the interface. A Operating System B Compiler C Implementation D Interpreter. 9 The functions which will give exact result when same arguments are passed are called. A Impure functions B Partial Functions,C Dynamic Functions D Pure functions.
XII Std Computer Science 8,Chapter 1 indd 8 20 02 2019 15 17 15. 10 The functions which cause side effects to the arguments passed are called. A impure function B Partial Functions,C Dynamic Functions D Pure functions. Answer the following questions 2 Marks,1 What is a subroutine. 2 Define Function with respect to Programming language. 3 Write the inference you get from X 78,4 Differentiate interface and implementation. 5 Which of the following is a normal function definition and which is recursive function. definition,i let rec sum x y,return x y,ii let disp.
print welcome,iii let rec sum num,if num 0 then return num sum num 1. return num,Answer the following questions 3 Marks,1 Mention the characteristics of Interface. 2 Why strlen is called pure function, 3 What is the side effect of impure function Give example. 4 Differentiate pure and impure function, 5 Wha happens if you modify a variable outside the function Give an example.


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