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Python Across Disciplines
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Table of Contents

1.1.   Introduction 1.2.   About the Author & Contact Info 1.3.   Book Conventions 1.4.   What (Who) is a Programmer? 1.5.   Programming Across Disciplines 1.6.   Foundational Computing Concepts 1.7.   About Python 1.8.   First Steps 1.8.1 Computer Setup 1.8.2 Python print() Function 1.8.3 Comments
2.1. About Data 2.2. Data Types 2.3. Variables 2.4. User Input 2.5. Data Structures (DS)         2.5.1. DS Concepts         2.5.2. Lists         2.5.3. Dictionaries         2.5.4. Others 2.6. Files         2.6.1. Files & File Systems         2.6.2. Python File Object         2.6.3. Data Files 2.7. Databases
3.1. About Processing 3.2. Decisions         3.2.1 Decision Concepts         3.2.2 Conditions & Booleans         3.2.3 if Statements         3.2.4 if-else Statements         3.2.5 if-elif-else Statements         3.2.6 In-Line if Statements 3.3. Repetition (a.k.a. Loops)         3.3.1  Repetition Concepts         3.3.2  while Loops         3.3.3  for Loops         3.3.4  Nested Loops         3.3.5  Validating User Input 3.4. Functions         3.4.1  Function Concepts         3.4.2  Built-In Functions         3.4.3  Programmer Defined Functions 3.5. Libraries         3.5.1  Library Concepts         3.5.2  Standard Library         3.5.3  External Libraries 3.6. Processing Case Studies         3.6.1  Case Studies         3.6.2  Parsing Data
4.1. About Output 4.2. Advanced Printing 4.3. Data Visualization   4.4  Sound
  4.5  Graphics
  4.6  Video
  4.7  Web Output
  4.8  PDFs & Documents
  4.9  Dashboards
  4.10  Animation & Games
  4.11  Text to Speech

5.1 About Disciplines 5.2 Accounting 5.3 Architecture 5.4 Art 5.5 Artificial Intelligence (AI) 5.6 Autonomous Vehicles 5.7 Bioinformatics 5.8 Biology 5.9 Bitcoin 5.10 Blockchain 5.11 Business 5.12 Business Analytics 5.13 Chemistry 5.14 Communication 5.15 Computational Photography 5.16 Computer Science 5.17 Creative Writing 5.18 Cryptocurrency 5.19 Cultural Studies 5.20 Data Analytics 5.21 Data Engineering 5.22 Data Science 5.23 Data Visualization 5.24 Drone Piloting 5.25 Economics 5.26 Education 5.27 Engineering 5.28 English 5.29 Entrepreneurship 5.30 Environmental Studies 5.31 Exercise Science 5.32 Film 5.33 Finance 5.34 Gaming 5.35 Gender Studies 5.36 Genetics 5.37 Geography 5.38 Geology 5.39 Geospatial Analysis ☯ 5.40 History 5.41 Humanities 5.42 Information Systems 5.43 Languages 5.44 Law 5.45 Linguistics 5.46 Literature 5.47 Machine Learning 5.48 Management 5.49 Marketing 5.50 Mathematics 5.51 Medicine 5.52 Military 5.53 Model Railroading 5.54 Music 5.55 Natural Language Processing (NLP) 5.56 Network Analysis 5.57 Neural Networks 5.58 Neurology 5.59 Nursing 5.60 Pharmacology 5.61 Philosophy 5.62 Physiology 5.63 Politics 5.64 Psychiatry 5.65 Psychology 5.66 Real Estate 5.67 Recreation 5.68 Remote Control (RC) Vehicles 5.69 Rhetoric 5.70 Science 5.71 Sociology 5.72 Sports 5.73 Stock Trading 5.74 Text Mining 5.75 Weather 5.76 Writing
6.1. Databases         6.1.1 Overview of Databases         6.1.2 SQLite Databases         6.1.3 Querying a SQLite Database         6.1.4 CRUD Operations with SQLite         6.1.5 Connecting to Other Databases
Built-In Functions Conceptss Data Types Date & Time Format Codes Dictionary Methods Escape Sequences File Access Modes File Object Methods Python Keywords List Methods Operators Set Methods String Methods Tuple Methods Glossary Index Appendices   Software Install & Setup
  Coding Tools:
  A.  Python ↗   B.  Google CoLaboratory ↗   C.  Visual Studio Code ↗   D.  PyCharm IDE ↗   E.  Git ↗   F.  GitHub ↗
  Database Tools:
  G.  SQLite Database ↗   H.  MySQL Database ↗


Python Across Disciplines
by John Gordon © 2023
Table of Contents
1.1.   Introduction 1.2.   About the Author & Contact Info 1.3.   Book Conventions 1.4.   What (Who) is a Programmer? 1.5.   Programming Across Disciplines 1.6.   Foundational Computing Concepts 1.7.   About Python 1.8.   First Steps         1.8.1. Computer Setup         1.8.2. Python print() Function         1.8.3. Comments
2.1. About Data 2.2. Data Types         2.2.1. Variables         2.2.2. Strings         2.2.3. Integers         2.2.4. Floating Points         2.2.5. Booleans 2.3. User Input 2.5. Data Structures (DS)         2.5.1. Introduction to DS         2.5.2. Lists         2.5.3. Dictionaries         2.5.4. Others     2.6. Files         2.6.1. Files & File Systems         2.6.2. Python File Object         2.6.3. Data Files 2.7. Databases
3.1. About Processing     3.2. Decisions         3.2.1 Decision Concepts         3.2.2 Conditions & Booleans         3.2.3 if Statements         3.2.4 if-else Statements         3.2.5 if-elif-else Statements         3.2.6 In-Line if Statements     3.3. Repetition (a.k.a. Loops)         3.3.1  Repetition Concepts         3.3.2  while Loops         3.3.3  for Loops         3.3.4  Nested Loops         3.3.5  Validating User Input     3.4. Functions         3.4.1  Function Concepts         3.4.2  Built-In Functions         3.4.3  Programmer Defined Functions     3.5. Libraries         3.5.1  Library Concepts         3.5.2  Standard Library         3.5.3  External Libraries     3.6. Processing Case Studies         3.6.1  Case Studies         3.6.2  Parsing Data             3.6.3  eCommerce Simulation         3.6.4  Datasets         3.6.5  Web Scraping             3.6.6  Named Entity Reconition         3.6.7  Automation
4.1. About Output 4.2. Advanced Printing 4.3. Data Visualization     4.4  Sound
    4.5  Graphics
    4.6  Video
    4.7  Web Output
    4.8  PDFs & Documents
    4.9  Dashboards
    4.10  Animation & Games
    4.11  Text to Speech

5.1 Disciplinarity 5.2 Accounting 5.3 Architecture 5.4 Art 5.5 Artificial Intelligence (AI) 5.6 Autonomous Vehicles 5.7 Bioinformatics 5.8 Biology 5.9 Bitcoin 5.10 Blockchain 5.11 Business 5.12 Business Analytics 5.13 Chemistry 5.14 Communication 5.15 Computational Photography 5.16 Computer Science 5.17 Creative Writing 5.18 Cryptocurrency 5.19 Cultural Studies 5.20 Data Analytics 5.21 Data Engineering 5.22 Data Science 5.23 Data Visualization 5.24 Drone Piloting 5.25 Economics 5.26 Education 5.27 Engineering 5.28 English 5.29 Entrepreneurship 5.30 Environmental Studies 5.31 Exercise Science 5.32 Film 5.33 Finance 5.34 Gaming 5.35 Gender Studies 5.36 Genetics 5.37 Geography 5.38 Geology 5.39 Geospatial Analysis       5.39.1 Geospatial Concepts       5.39.2 Geospatial in the Humanities       5.39.3 Geospatial Project Ideas       5.39.4 Geospatial Data Sources 5.40 History 5.41 Humanities 5.42 Information Systems 5.43 Languages 5.44 Law 5.45 Linguistics 5.46 Literature 5.47 Machine Learning 5.48 Management 5.49 Marketing 5.50 Mathematics 5.51 Medicine 5.52 Military 5.53 Model Railroading 5.54 Music 5.55 Natural Language Processing 5.56 Network Analysis 5.57 Neural Networks 5.58 Neurology 5.59 Nursing 5.60 Pharmacology 5.61 Philosophy 5.62 Physiology 5.63 Politics 5.64 Psychiatry 5.65 Psychology 5.66 Real Estate 5.67 Recreation 5.68 Remote Control (RC) Vehicles 5.69 Rhetoric 5.70 Science 5.71 Sociology 5.72 Sports 5.73 Stock Trading 5.74 Text Mining 5.75 Weather 5.76 Writing
6.0 Chapter Overview     6.1. Databases
        6.1.1 Overview of Databases         6.1.2 SQLite Databases         6.1.3 Querying a SQLite Database         6.1.4 CRUD Operations w/SQLite         6.1.5 Connecting to Other Databases     6.2. Object Oriented Programming
            6.2.1. Introduction to OOP             6.2.2. Unified Modeling Language             6.2.3. Classes & Objects             6.2.4. Abstraction             6.2.5. Encapsulation             6.2.6. Inheritance             6.2.7. Polymorphism             6.2.8. Exception Handling             6.2.9. Codealong: Employees             6.2.10. Codealong: Cars     6.3. Graphical User Interfaces
            6.3.1. Introduction to GUIs
            6.3.2. Tkinter
            6.3.3. Codealong: Login Form
            6.3.4. Codealong: Data Entry Form
    6.4. Algorithms & Data Structures
            6.4.1. Introduction to Algorithms
            6.4.2. Searching
            6.4.3. Sorting
            6.4.4. Metrics
            6.4.5. Nodes
            6.4.6. Linked Lists 1
            6.4.7. Linked Lists 2
            6.4.8. Stacks
            6.4.9. Queues
            6.4.10. Heaps
            6.4.11. Trees
            6.4.12. Graphs
            6.4.13. Maps
            6.4.14. Hashing
            6.4.15. Cryptography
    6.5. Additional Advanced Topics
            6.5.1. APIs
            6.5.2. Automation
            6.5.3. Recursion
            6.5.4. More About Datasets
            6.5.5. Large Language Models
            6.5.6. Text Analysis
            6.5.7. Web Scraping
            6.5.8. Data Science
            6.5.9. Machline Learning
            6.5.10. Natural Lang Processing
            6.5.11. Artificial Intelligence
            6.5.12. Cython
            6.5.13. PyPy
            6.5.14. Multi-Threading
            6.5.15. Parallel Processing

Built-In Functions ↗ Concepts: Alphabetical ↗ Concepts: By Chapter ↗ Data Types ↗ Date & Time Format Codes ↗ Dictionary Methods ↗ Escape Sequences ↗ File Access Modes ↗ File Object Methods ↗ Python Keywords ↗ List Methods ↗ Operators ↗ Set Methods ↗ String Formatting Types ↗ String Methods ↗ Tuple Methods ↗
  Software Install & Setup

  Coding Tools:
  A.  Python ↗   B.  Google CoLaboratory ↗   C.  Visual Studio Code ↗   D.  PyCharm IDE ↗   E.  Git ↗   F.  GitHub ↗
  Database Tools:
  G.  SQLite Database ↗   H.  MySQL Database ↗



Table of Contents  »  Reference Materials : File Access Modes

File Access Modes

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Python file access modes are used when opening a file with the built-in open() function, determining how the file will be accessed and manipulated. The primary modes include 'r' for reading (default mode), 'w' for writing (overwrites existing file or creates a new one), 'a' for appending (writes data to the end of the file if it exists), and 'x' for exclusive creation (fails if the file already exists). In addition to these, you can add a 'b' to open the file in binary mode (e.g., 'rb', 'wb') for non-text files like images or videos, and a '+' for updating (reading and writing simultaneously, e.g., 'r+', 'w+'). Each mode serves a specific purpose, allowing controlled interaction with files, ranging from simple text reading to complex binary data manipulation. Understanding and selecting the appropriate access mode is crucial for effective file handling in Python.


File Access Mode Description
r
Opens the specified file for read only access. Upon opening the file pointer is positioned at the very beginning of the file. If file_access_mode is left out of the open() statement, this is the default access mode.
rb
Opens the specified file for binary read only access. Upon opening, the file pointer is positioned at the very beginning of the file.
r+
Opens the specified file for both read and write access. Upon opening, the file pointer is positioned at the very beginning of the file.
rb+
Opens the specified binary file for both read and write access. Upon opening, the file pointer is positioned at the very beginning of the file.
w
Opens the specified file for writing only. If the file exists already at the location specified, the existing file is overwritten. If the file does not exist already, the file is created with the name specified.
wb
Opens the specified binary file for writing only. If the file exists already at the location specified, the existing file is overwritten. If the file does not exist already, the file is created with the name specified.
w+
Opens the specified file for both reading and writing. If the file exists already at the location specified, the existing file is overwritten. If the file does not exist already, the file is created with the name specified.
wb+
Opens the specified binary file for both reading and writing. If the file exists already at the location specified, the existing file is overwritten. If the file does not exist already, the file is created with the name specified.
a
Opens the specified file for appending. If the file exists, the file pointer is positioned at the end of the file and the file is set to append mode, that is, any new data written to the file will be appended (added) to the end of the file. If the specified file does not already exist, then the file is created using the file name specified, the file pointer will be at the beginning of the empty file and the file will be set for writing.
ab
Opens the specified binary file for appending. If the file exists, the file pointer is positioned at the end of the file and the file is set to append mode, that is, any new data written to the file will be appended (added) to the end of the file. If the specified file does not already exist, then the file is created using the file name specified, the file pointer will be at the beginning of the empty file and the file will be set for writing.
a+
Opens the specified file for appending and reading. If the file exists, the file pointer is positioned at the end of the file and the file is set to append mode, that is, any new data written to the file will be appended (added) to the end of the file. If the specified file does not already exist, then the file is created using the file name specified, the file pointer will be at the beginning of the empty file and the file will be set for writing.
ab+
Opens the specified binary file for appending and reading. If the file exists, the file pointer is positioned at the end of the file and the file is set to append mode, that is, any new data written to the file will be appended (added) to the end of the file. If the specified file does not already exist, then the file is created using the file name specified, the file pointer will be at the beginning of the empty file and the file will be set for writing.






© 2023 John Gordon
Cascade Street Publishing, LLC