Table of Contents. Preface... xxi

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1 Table of Contents Preface... xxi Chapter 1: Introduction to Python... 1 Python... 2 Features of Python... 3 Execution of a Python Program... 7 Viewing the Byte Code... 9 Flavors of Python Python Virtual Machine (PVM) Frozen Binaries Memory Management in Python Garbage Collection in Python Comparisons between C and Python Comparisons between Java and Python Points to Remember Chapter 2: Writing Our First Python Program Installing Python for Windows Testing the Installation in Windows Installing numpy Setting the Path to Python Writing Our First Python Program Executing a Python Program Using Python s Command Line Window Using Python s IDLE Graphics Window Running Directly from System Prompt Getting Help in Python Getting Python Documentation Help Reopening the Python Program in IDLE Points to Remember Chapter 3: Datatypes in Python Comments in Python Single line comments Multi line comments... 46

2 x Core Python Docstrings How Python Sees Variables Datatypes in Python Built-in datatypes The None Type Numeric Types Representing Binary, Octal and Hexadecimal Numbers Converting the Datatypes Explicitly bool Datatype Sequences in Python str Datatype bytes Datatype bytearray Datatype list Datatype tuple Datatype range Datatype Sets set Datatype frozenset Datatype Mapping Types Literals in Python Numeric Literals Boolean Literals String Literals Determining the Datatype of a Variable What about Characters User-defined Datatypes Constants in Python Identifiers and Reserved words Naming Conventions in Python Points to Remember Chapter 4: Operators in Python Operator Arithmetic Operators Using Python Interpreter as Calculator Assignment Operators Unary Minus Operator Relational Operators... 75

3 Table of Contents xi Logical Operators Boolean Operators Bitwise Operators Bitwise Complement Operator ( ~ ) Bitwise AND Operator (&) Bitwise OR Operator ( ) Bitwise XOR Operator ( ^ ) Bitwise Left Shift Operator (<<) Bitwise Right Shift Operator (>>) Membership Operators The in Operator The not in Operator Identity Operators The is Operator The is not Operator Operator Precedence and Associativity Mathematical Functions Using IDLE Window Using Command Line Window Executing at System Prompt Points to Remember Chapter 5: Input and Output Output statements The print() Statement The print( string ) Statement The print(variables list) Statement The print(object) Statement The print( string, variables list) Statement The print(formatted string) Statement Input Statements Command Line Arguments Parsing Command Line Arguments Points to Remember Chapter 6: Control Statements Control Statements The if Statement A Word on Indentation

4 xii Core Python The if else Statement The if elif else Statement The while Loop The for Loop Infinite Loops Nested Loops The else Suite The break Statement The continue Statement The pass Statement The assert Statement The return Statement Points to Remember Chapter 7: Arrays in Python Array Advantages of Arrays Creating an Array Importing the Array Module Indexing and Slicing on Arrays Processing the Arrays Types of Arrays Working with Arrays using numpy Creating Arrays using array() Creating Arrays using linspace Creating Arrays using logspace Creating Arrays using arange() Function Creating Arrays using zeros() and ones() Functions Mathematical Operations on Arrays Comparing Arrays Aliasing the Arrays Viewing and Copying Arrays Slicing and Indexing in numpy Arrays Dimensions of Arrays Attributes of an Array The ndim Attribute The shape Attribute The size Attribute The itemsize Attribute

5 Table of Contents xiii The dtype Attribute The nbytes Attribute The reshape() Method The flatten() Method Working with Multi-dimensional Arrays The array() Function The ones() and zeros() Functions The eye() Function The reshape() Function Indexing in Multi-dimensional Arrays Slicing the Multi-dimensional Arrays Matrices in numpy Getting Diagonal Elements of a Matrix Finding Maximum and Minimum Elements Finding Sum and Average of Elements Products of Elements Sorting the Matrix Transpose of a Matrix Matrix Addition and Multiplication Random Numbers Points to Remember Chapter 8: Strings and Characters Creating Strings Length of a String Indexing in Strings Slicing the Strings Repeating the Strings Concatenation of Strings Checking Membership Comparing Strings Removing Spaces from a String Finding Sub Strings Counting Substrings in a String Strings are Immutable Replacing a String with another String Splitting and Joining Strings Changing Case of a String Checking Starting and Ending of a String

6 xiv Core Python String Testing Methods Formatting the Strings Working with Characters Sorting Strings Searching in the Strings Finding Number of Characters and Words Inserting Sub String into a String Points to Remember Chapter 9: Functions Difference between a Function and a Method Defining a Function Calling a Function Returning Results from a Function Returning Multiple Values from a Function Functions are First Class Objects Pass by Object Reference Formal and Actual Arguments Positional Arguments Keyword Arguments Default Arguments Variable Length Arguments Local and Global Variables The Global Keyword Passing a Group of Elements to a Function Recursive Functions Anonymous Functions or Lambdas Using Lambdas with filter() Function Using Lambdas with map() Function Using Lambdas with reduce() Function Function Decorators Generators Structured Programming Creating our Own Modules in Python The Special Variable name Points to Remember Chapter 10: Lists and Tuples List Creating Lists using range() Function

7 Table of Contents xv Updating the Elements of a List Concatenation of Two Lists Repetition of Lists Membership in Lists Aliasing and Cloning Lists Methods to Process Lists Finding Biggest and Smallest Elements in a List Sorting the List Elements Number of Occurrences of an Element in the List Finding Common Elements in Two Lists Storing Different Types of Data in a List Nested Lists Nested Lists as Matrices List Comprehensions Tuples Creating Tuples Accessing the Tuple Elements Basic Operations on Tuples Functions to Process Tuples Nested Tuples Inserting Elements in a Tuple Modifying Elements of a Tuple Deleting Elements from a Tuple Points to Remember Chapter 11: Dictionaries Operations on Dictionaries Dictionary Methods Using for Loop with Dictionaries Sorting the Elements of a Dictionary using Lambdas Converting Lists into Dictionary Converting Strings into Dictionary Passing Dictionaries to Functions Ordered Dictionaries Points to Remember Chapter 12: Introduction to Oops Problems in Procedure Oriented Approach Specialty of Python Language Features of Object Oriented Programming System (OOPS)

8 xvi Core Python Classes and Objects Encapsulation Abstraction Inheritance Polymorphism Points to Remember Chapter 13: Classes and Objects Creating a Class The Self Variable Constructor Types of Variables Namespaces Types of Methods Instance Methods Class Methods Static Methods Passing Members of One Class to Another Class Inner Classes Points to Remember Chapter 14: Inheritance and Polymorphism Constructors in Inheritance Overriding Super Class Constructors and Methods The super() Method Types of Inheritance Single Inheritance Multiple Inheritance Method Resolution Order (MRO) Polymorphism Duck Typing Philosophy of Python Operator Overloading Method Overloading Method Overriding Points to Remember Chapter 15: Abstract Classes and Interfaces Abstract Method and Abstract Class Interfaces in Python

9 Table of Contents xvii Abstract Classes vs. Interfaces Points to Remember Chapter 16: Exceptions Errors in a Python Program Compile-Time Errors Runtime Errors Logical Errors Exceptions Exception Handling Types of Exceptions The Except Block The assert Statement User-Defined Exceptions Logging the Exceptions Points to Remember Chapter 17: Files in Python Files Types of Files in Python Opening a File Closing a File Working with Text Files Containing Strings Knowing Whether a File Exists or Not Working with Binary Files The with Statement Pickle in Python The seek() and tell() Methods Random Accessing of Binary Files Random Accessing of Binary Files using mmap Zipping and Unzipping Files Working with Directories Running Other Programs from Python Program Points to Remember Chapter 18: Regular Expressions in Python Regular Expressions Sequence Characters in Regular Expressions Quantifiers in Regular Expressions Special Characters in Regular Expressions

10 xviii Core Python Using Regular Expressions on Files Retrieving Information from a HTML File Points to Remember Chapter 19: Data Structures in Python Linked Lists Stacks Queues Deques Points to Remember Chapter 20: Date and Time The epoch Date and Time Now Combining Date and Time Formatting Dates and Times Finding Durations using timedelta Comparing Two Dates Sorting Dates Stopping Execution Temporarily Knowing the Time taken by a Program Working with Calendar Module Points to Remember Chapter 21: Threads Single Tasking Multitasking Differences between a Process and a Thread Concurrent Programming and GIL Uses of Threads Creating Threads in Python Creating a Thread without using a Class Creating a Thread by Creating a Sub Class to Thread Class Creating a Thread without Creating Sub Class to Thread Class Thread Class Methods Single Tasking using a Thread Multitasking using Multiple Threads Thread Synchronization Locks Semaphore

11 Table of Contents xix Deadlock of Threads Avoiding Deadlocks in a Program Communication between Threads Thread Communication using nofity() and wait() Methods Thread Communication using a Queue Daemon Threads Points to Remember Chapter 22: Graphical User Interface GUI in Python The Root Window Fonts and Colors Working with Containers Canvas Frame Widgets Button Widget Arranging Widgets in the Frame Label Widget Message Widget Text Widget Scrollbar Widget Checkbutton Widget Radiobutton Widget Entry Widget Spinbox Widget Listbox Widget Menu Widget Points to Remember Chapter 23: Networking in Python Protocol TCP/IP Protocol User Datagram Protocol (UDP) Sockets Knowing IP Address URL Reading the Source Code of a Web Page Downloading a Web Page from Internet Downloading an Image from Internet

12 xx Core Python A TCP/IP Server A TCP/IP Client A UDP Server A UDP Client File Server File Client Two-Way Communication between Server and Client Sending a Simple Mail Points to Remember Chapter 24: Python s Database Connectivity DBMS Advantages of a DBMS over Files Types of Databases Used with Python Installation of MySQL Database Software Setting the Path to MySQL Server Verifying MySQL in the Windows Operating System Installing MySQL Connector Verifying the Connector Installation Working with MySQL Database Using MySQL from Python Retrieving All Rows from a Table Inserting Rows into a Table Deleting Rows from a Table Updating Rows in a Table Creating Database Tables through Python Installation of Oracle 11g Verifying Oracle Installation in Windows Operating System Installing Oracle Database Driver Verifying the Driver Installation Working with Oracle Database Using Oracle Database from Python Stored Procedures Points to Remember Program Index