Supercharged Python: Take Your Code to the Next Level

Cover
Title Page
Copyright Page
Contents
Preface
What Makes Python Special?
Paths to Learning: Where Do I Start?
Clarity and Examples Are Everything
Learning Aids: Icons
What You’ll Learn
Have Fun
Acknowledgments
About the Authors

Chapter 1 Review of the Fundamentals
____1.1 Python Quick Start
____1.2 Variables and Naming Names
____1.3 Combined Assignment Operators
____1.4 Summary of Python Arithmetic Operators
____1.5 Elementary Data Types: Integer and Floating Point
____1.6 Basic Input and Output
____1.7 Function Definitions
____1.8 The Python “if” Statement
____1.9 The Python “while” Statement
____1.10 A Couple of Cool Little Apps
____1.11 Summary of Python Boolean Operators
____1.12 Function Arguments and Return Values
____1.13 The Forward Reference Problem
____1.14 Python Strings
____1.15 Python Lists (and a Cool Sorting App)
____1.16 The “for” Statement and Ranges
____1.17 Tuples
____1.18 Dictionaries
____1.19 Sets
____1.20 Global and Local Variables
____Summary
____Review Questions
____Suggested Problems


Chapter 2 Advanced String Capabilities
____2.1 Strings Are Immutable
____2.2 Numeric Conversions, Including Binary
____2.3 String Operators (+, =, *, >, etc.)
____2.4 Indexing and Slicing
____2.5 Single-Character Functions (Character Codes)
____2.6 Building Strings Using “join”
____2.7 Important String Functions
____2.8 Binary, Hex, and Octal Conversion Functions
____2.9 Simple Boolean (“is”) Methods
____2.10 Case Conversion Methods
____2.11 Search-and-Replace Methods
____2.12 Breaking Up Input Using “split”
____2.13 Stripping
____2.14 Justification Methods
____Summary
____Review Questions
____Suggested Problems


Chapter 3 Advanced List Capabilities
____3.1 Creating and Using Python Lists
____3.2 Copying Lists Versus Copying List Variables
____3.3 Indexing
________3.3.1 Positive Indexes
________3.3.2 Negative Indexes
________3.3.3 Generating Index Numbers Using “enumerate”
____3.4 Getting Data from Slices
____3.5 Assigning into Slices
____3.6 List Operators
____3.7 Shallow Versus Deep Copying
____3.8 List Functions
____3.9 List Methods: Modifying a List
____3.10 List Methods: Getting Information on Contents
____3.11 List Methods: Reorganizing
____3.12 Lists as Stacks: RPN Application
____3.13 The “reduce” Function
____3.14 Lambda Functions
____3.15 List Comprehension
____3.16 Dictionary and Set Comprehension
____3.17 Passing Arguments Through a List
____3.18 Multidimensional Lists
________3.18.1 Unbalanced Matrixes
________3.18.2 Creating Arbitrarily Large Matrixes
____Summary
____Review Questions
____Suggested Problems


Chapter 4 Shortcuts, Command Line, and Packages
____4.1 Overview
____4.2 Twenty-Two Programming Shortcuts
________4.2.1 Use Python Line Continuation as Needed
________4.2.2 Use “for” Loops Intelligently
________4.2.3 Understand Combined Operator Assignment (+= etc.)
________4.2.4 Use Multiple Assignment
________4.2.5 Use Tuple Assignment
________4.2.6 Use Advanced Tuple Assignment
________4.2.7 Use List and String “Multiplication”
________4.2.8 Return Multiple Values
________4.2.9 Use Loops and the “else” Keyword
________4.2.10 Take Advantage of Boolean Values and “not”
________4.2.11 Treat Strings as Lists of Characters
________4.2.12 Eliminate Characters by Using “replace”
________4.2.13 Don’t Write Unnecessary Loops
________4.2.14 Use Chained Comparisons (n < x< m)
________4.2.15 Simulate “switch” with a Table of Functions
________4.2.16 Use the “is” Operator Correctly
________4.2.17 Use One-Line “for” Loops
________4.2.18 Squeeze Multiple Statements onto a Line
________4.2.19 Write One-Line if/then/else Statements
________4.2.20 Create Enum Values with “range”
________4.2.21 Reduce the Inefficiency of the “print” Function Within IDLE
________4.2.22 Place Underscores Inside Large Numbers
____4.3 Running Python from the Command Line
________4.3.1 Running on a Windows-Based System
________4.3.2 Running on a Macintosh System
________4.3.3 Using pip or pip3 to Download Packages
____4.4 Writing and Using Doc Strings
____4.5 Importing Packages
____4.6 A Guided Tour of Python Packages
____4.7 Functions as First-Class Objects
____4.8 Variable-Length Argument Lists
________4.8.1 The *args List
________4.8.2 The “**kwargs” List
____4.9 Decorators and Function Profilers
____4.10 Generators
________4.10.1 What’s an Iterator?
________4.10.2 Introducing Generators
____4.11 Accessing Command-Line Arguments
____Summary
____Questions for Review
____Suggested Problems


Chapter 5 Formatting Text Precisely
____5.1 Formatting with the Percent Sign Operator (%)
____5.2 Percent Sign (%) Format Specifiers
____5.3 Percent Sign (%) Variable-Length Print Fields
____5.4 The Global “format” Function
____5.5 Introduction to the “format” Method
____5.6 Ordering by Position (Name or Number)
____5.7 “Repr” Versus String Conversion
____5.8 The “spec” Field of the “format” Function and Method
________5.8.1 Print-Field Width
________5.8.2 Text Justification: “fill” and “align” Characters
________5.8.3 The “sign” Character
________5.8.4 The Leading-Zero Character (0)
________5.8.5 Thousands Place Separator
________5.8.6 Controlling Precision
________5.8.7 “Precision” Used with Strings (Truncation)
________5.8.8 “Type” Specifiers
________5.8.9 Displaying in Binary Radix
________5.8.10 Displaying in Octal and Hex Radix
________5.8.11 Displaying Percentages
________5.8.12 Binary Radix Example
____5.9 Variable-Size Fields
____Summary
____Review Questions
____Suggested Problems


Chapter 6 Regular Expressions, Part I
____6.1 Introduction to Regular Expressions
____6.2 A Practical Example: Phone Numbers
____6.3 Refining Matches
____6.4 How Regular Expressions Work: Compiling Versus Running
____6.5 Ignoring Case, and Other Function Flags
____6.6 Regular Expressions: Basic Syntax Summary
________6.6.1 Meta Characters
________6.6.2 Character Sets
________6.6.3 Pattern Quantifiers
________6.6.4 Backtracking, Greedy, and Non-Greedy
____6.7 A Practical Regular-Expression Example
____6.8 Using the Match Object
____6.9 Searching a String for Patterns
____6.10 Iterative Searching (“findall”)
____6.11 The “findall” Method and the Grouping Problem
____6.12 Searching for Repeated Patterns
____6.13 Replacing Text
____Summary
____Review Questions
____Suggested Problems


Chapter 7 Regular Expressions, Part II
____7.1 Summary of Advanced RegEx Grammar
____7.2 Noncapture Groups
________7.2.1 The Canonical Number Example
________7.2.2 Fixing the Tagging Problem
____7.3 Greedy Versus Non-Greedy Matching
____7.4 The Look-Ahead Feature
____7.5 Checking Multiple Patterns (Look-Ahead)
____7.6 Negative Look-Ahead
____7.7 Named Groups
____7.8 The “re.split” Function
____7.9 The Scanner Class and the RPN Project
____7.10 RPN: Doing Even More with Scanner
____Summary
____Review Questions
____Suggested Problems


Chapter 8 Text and Binary Files
____8.1 Two Kinds of Files: Text and Binary
________8.1.1 Text Files
________8.1.2 Binary Files
____8.2 Approaches to Binary Files: A Summary
____8.3 The File/Directory System
____8.4 Handling File-Opening Exceptions
____8.5 Using the “with” Keyword
____8.6 Summary of Read/Write Operations
____8.7 Text File Operations in Depth
____8.8 Using the File Pointer (“seek”)
____8.9 Reading Text into the RPN Project
________8.9.1 The RPN Interpreter to Date
________8.9.2 Reading RPN from a Text File
________8.9.3 Adding an Assignment Operator to RPN
____8.10 Direct Binary Read/Write
____8.11 Converting Data to Fixed-Length Fields (“struct”)
________8.11.1 Writing and Reading One Number at a Time
________8.11.2 Writing and Reading Several Numbers at a Time
________8.11.3 Writing and Reading a Fixed-Length String
________8.11.4 Writing and Reading a Variable-Length String
________8.11.5 Writing and Reading Strings and Numerics Together
________8.11.6 Low-Level Details: Big Endian Versus Little Endian
____8.12 Using the Pickling Package
____8.13 Using the “shelve” Package
____Summary
____Review Questions
____Suggested Problems


Chapter 9 Classes and Magic Methods
____9.1 Classes and Objects: Basic Syntax
____9.2 More About Instance Variables
____9.3 The “_ _init_ _” and “_ _new_ _” Methods
____9.4 Classes and the Forward Reference Problem
____9.5 Methods Generally
____9.6 Public and Private Variables and Methods
____9.7 Inheritance
____9.8 Multiple Inheritance
____9.9 Magic Methods, Summarized
____9.10 Magic Methods in Detail
________9.10.1 String Representation in Python Classes
________9.10.2 The Object Representation Methods
________9.10.3 Comparison Methods
________9.10.4 Arithmetic Operator Methods
________9.10.5 Unary Arithmetic Methods
________9.10.6 Reflection (Reverse-Order) Methods
________9.10.7 In-Place Operator Methods
________9.10.8 Conversion Methods
________9.10.9 Collection Class Methods
________9.10.10 Implementing “_ _iter_ _” and “_ _next_ _”
____9.11 Supporting Multiple Argument Types
____9.12 Setting and Getting Attributes Dynamically
____Summary
____Review Questions
____Suggested Problems


Chapter 10 Decimal, Money, and Other Classes
____10.1 Overview of Numeric Classes
____10.2 Limitations of Floating-Point Format
____10.3 Introducing the Decimal Class
____10.4 Special Operations on Decimal Objects
____10.5 A Decimal Class Application
____10.6 Designing a Money Class
____10.7 Writing the Basic Money Class (Containment)
____10.8 Displaying Money Objects (“_ _str_ _”, “_ _repr_ _”)
____10.9 Other Monetary Operations
____10.10 Demo: A Money Calculator
____10.11 Setting the Default Currency
____10.12 Money and Inheritance
____10.13 The Fraction Class
____10.14 The Complex Class
____Summary
____Review Questions
____Suggested Problems


Chapter 11 The Random and Math Packages
____11.1 Overview of the Random Package
____11.2 A Tour of Random Functions
____11.3 Testing Random Behavior
____11.4 A Random-Integer Game
____11.5 Creating a Deck Object
____11.6 Adding Pictograms to the Deck
____11.7 Charting a Normal Distribution
____11.8 Writing Your Own Random-Number Generator
________11.8.1 Principles of Generating Random Numbers
________11.8.2 A Sample Generator
____11.9 Overview of the Math Package
____11.10 A Tour of Math Package Functions
____11.11 Using Special Values (pi)
____11.12 Trig Functions: Height of a Tree
____11.13 Logarithms: Number Guessing Revisited
________11.13.1 How Logarithms Work
________11.13.2 Applying a Logarithm to a Practical Problem
____Summary
____Review Questions
____Suggested Problems


Chapter 12 The “numpy” (Numeric Python) Package
____12.1 Overview of the “array,” “numpy,” and “matplotlib” Packages
________12.1.1 The “array” Package
________12.1.2 The “numpy” Package
________12.1.3 The “numpy.random” Package
________12.1.4 The “matplotlib” Package
____1 2.2 Using the “array” Package
____12.3 Downloading and Importing “numpy”
____12.4 Introduction to “numpy”: Sum 1 to 1 Million
____12.5 Creating “numpy” Arrays
________12.5.1 The “array” Function (Conversion to an Array)
________12.5.2 The “arange” Function
________12.5.3 The “linspace” Function
________12.5.4 The “empty” Function
________12.5.5 The “eye” Function
________12.5.6 The “ones” Function
________12.5.7 The “zeros” Function
________12.5.8 The “full” Function
________12.5.9 The “copy” Function
________12.5.10 The “fromfunction” Function
____12.6 Example: Creating a Multiplication Table
____12.7 Batch Operations on “numpy” Arrays
____12.8 Ordering a Slice of “numpy”
____12.9 Multidimensional Slicing
____12.10 Boolean Arrays: Mask Out That “numpy”!
____12.11 “numpy” and the Sieve of Eratosthenes
____12.12 Getting “numpy” Stats (Standard Deviation)
____1 2.13 Getting Data on “numpy” Rows and Columns
____Summary
____Review Questions
____Suggested Problems


Chapter 13 Advanced Uses of “numpy”
____13.1 Advanced Math Operations with “numpy”
____13.2 Downloading “mat plotlib”
____13.3 Plotting Lines with “numpy” and “matplotlib”
____13.4 Plotting More Than One Line
____13.5 Plotting Compound Interest
____13.6 Creating Histograms with “matplotlib”
____13.7 Circles and the Aspect Ratio
____13.8 Creating Pie Charts
____13.9 Doing Linear Algebra with “numpy”
________13.9.1 The Dot Product
________13.9.2 The Outer-Product Function
________13.9.3 Other Linear Algebra Functions
____13.10 Three-Dimensional Plotting
____13.11 “numpy” Financial Applications
____13.12 Adjusting Axes with “xticks” and “yticks”
____13.13 “numpy” Mixed-Data Records
____13.14 Reading and Writing “numpy” Data from Files
____Summary
____Review Questions
____Suggested Problems


Chapter 14 Multiple Modules and the RPN Example
____14.1 Overview of Modules in Python
____14.2 Simple Two-Module Example
____14.3 Variations on the “import” Statement
____14.4 Using the “_ _all_ _” Symbol
____14.5 Public and Private Module Variables
____14.6 The Main Module and “_ _main_ _”
____14.7 Gotcha! Problems with Mutual Importing
____14.8 RPN Example: Breaking into Two Modules
____14.9 RPN Example: Adding I/O Directives
____14.10 Further Changes to the RPN Example
________14.10.1 Adding Line-Number Checking
________14.10.2 Adding Jump-If-Not-Zero
________14.10.3 Greater-Than (>) and Get-Random-Number (!)
____14.11 RPN: Putting It All Together
____Summary
____Review Questions
____Suggested Problems


Chapter 15 Getting Financial Data off the Internet
____15.1 Plan of This Chapter
____15.2 Introducing the Pandas Package
____15.3 “stock_load”: A Simple Data Reader
____15.4 Producing a Simple Stock Chart
____15.5 Adding a Title and Legend
____15.6 Writing a “makeplot” Function (Refactoring)
____15.7 Graphing Two Stocks Together
____15.8 Variations: Graphing Other Data
____15.9 Limiting the Time Period
____15.10 Split Charts: Subplot the Volume
____15.11 Adding a Moving-Average Line
____15.12 Giving Choices to the User
____Summary
____Review Questions
____Suggested Problems


Appendix A: Python Operator Precedence Table
Appendix B: Built-In Python Functions
____abs(x)
____all(iterable)
____any(iterable)
____ascii(obj)
____bin(n)
____bool(obj)
____bytes(source, encoding)
____callable(obj)
____chr(n)
____compile(cmd_str, filename, mode_str, flags=0, dont_inherit=False, optimize=–1)
____complex(real=0, imag=0)
____complex(complex_str)
____delattr(obj, name_str)
____dir([obj])
____divmod(a, b)
____enumerate(iterable, start=0)
____eval(expr_str [, globals [,locals]] )
____exec(object [, global [,locals]])
____filter(function, iterable)
____float([x])
____format(obj, [format_spec])
____frozenset([iterable])
____getattr(obj, name_str [,default])
____globals()
____hasattr(obj, name_str)
____hash(obj)
____help([obj])
____hex(n)
____id(obj)
____input([prompt_str])
____int(x, base=10)
____int()
____isinstance(obj, class)
____issubclass(class1, class2)
____iter(obj)
____len(sequence)
____list([iterable])
____locals()
____map(function, iterable1 [, iterable2…])
____max(arg1 [, arg2]…)
____max(iterable)
____min(arg1 [, arg2]…)
____min(iterable)
____oct(n)
____open(file_name_str, mode=\'rt\')
____ord(char_str)
____pow(x, y[, z])
____print(objects, sep=\'\', end=\'\\n\', file=sys.stdout)
____range(n)
____range(start, stop [, step])
____repr(obj)
____reversed(iterable)
____round(x [,ndigits])
____set([iterable])
____setattr(obj, name_str, value)
____sorted(iterable [, key] [, reverse])
____str(obj=\'\')
____str(obj=b\'\' [, encoding=\'utf-8\'])
____sum(iterable [, start])
____super(type)
____tuple([iterable])
____type(obj)
____zip(*iterables)

Appendix C: Set Methods
____set_obj.add(obj)
____set_obj.clear()
____set_obj.copy()
____set_obj.difference(other_set)
____set_obj.difference_update(other_set)
____set_obj.discard(obj)
____set_obj.intersection(other_set)
____set_obj.intersection_update(other_set)
____set_obj.isdisjoint(other_set)
____set_obj.issubset(other_set)
____set_obj.issuperset(other_set)
____set_obj.pop()
____set_obj.remove(obj)
____set_obj.symmetric_difference(other_set)
____set_obj.symmetric_difference_update(other_set)
____set_obj.union(other_set)
____set_obj.union_update(other_set)

Appendix D: Dictionary Methods
____dict_obj.clear()
____dict_obj.copy()
____dict_obj.get(key_obj, default_val = None)
____dict_obj.items()
____dict_obj.keys()
____dict_obj.pop(key [, default_value])
____dict_obj.popitem()
____dict_obj.setdefault(key, default_value=None)
____dict_obj.values()
____dict_obj.update(sequence)

Appendix E: Statement Reference
____Variables and Assignments
____Spacing Issues in Python
____Alphabetical Statement Reference
________assert Statement
________break Statement
________class Statement
________continue Statement
________def Statement
________del Statement
________elif Clause
________else Clause
________except Clause
________for Statement
________global Statement
________if Statement
________import Statement
________nonlocal Statement
________pass Statement
________raise Statement
________return Statement
________try Statement
________while Statement
________with Statement
________yield Statement

Index