GNU Octave

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GNU Octave
Preface
- Acknowledgements
- How You Can Contribute to Octave
- Distribution
1 A Brief Introduction to Octave
- 1.1 Running Octave
- 1.2 Simple Examples
- 1.3 Conventions
2 Getting Started
- 2.1 Invoking Octave from the Command Line
  - 2.1.1 Command Line Options
  - 2.1.2 Startup Files
- 2.2 Quitting Octave
- 2.3 Commands for Getting Help
- 2.4 Command Line Editing
- 2.5 How Octave Reports Errors
- 2.6 Executable Octave Programs
- 2.7 Comments in Octave Programs
3 Data Types
- 3.1 Built-in Data Types
- 3.2 User-defined Data Types
- 3.3 Object Sizes
4 Numeric Data Types
- 4.1 Matrices
  - 4.1.1 Empty Matrices
- 4.2 Ranges
- 4.3 Single Precision Data Types
- 4.4 Integer Data Types
  - 4.4.1 Integer Arithmetic
- 4.5 Bit Manipulations
- 4.6 Logical Values
- 4.7 Promotion and Demotion of Data Types
- 4.8 Predicates for Numeric Objects
5 Strings
- 5.1 Escape Sequences in String Constants
- 5.2 Character Arrays
- 5.3 Creating Strings
  - 5.3.1 Concatenating Strings
  - 5.3.2 Conversion of Numerical Data to Strings
- 5.4 Comparing Strings
- 5.5 Manipulating Strings
- 5.6 String Conversions
- 5.7 Character Class Functions
6 Data Containers
- 6.1 Structures
- 6.2 Cell Arrays
- 6.3 Comma Separated Lists
  - 6.3.1 Comma Separated Lists Generated from Cell Arrays
  - 6.3.2 Comma Separated Lists Generated from Structure Arrays
7 Variables
- 7.1 Global Variables
- 7.2 Persistent Variables
- 7.3 Status of Variables
8 Expressions
- 8.1 Index Expressions
  - 8.1.1 Advanced Indexing
- 8.2 Calling Functions
  - 8.2.1 Call by Value
  - 8.2.2 Recursion
- 8.3 Arithmetic Operators
- 8.4 Comparison Operators
- 8.5 Boolean Expressions
  - 8.5.1 Element-by-element Boolean Operators
  - 8.5.2 Short-circuit Boolean Operators
- 8.6 Assignment Expressions
- 8.7 Increment Operators
- 8.8 Operator Precedence
9 Evaluation
- 9.1 Calling a Function by its Name
- 9.2 Evaluation in a Different Context
10 Statements
- 10.1 The if Statement
- 10.2 The switch Statement
  - 10.2.1 Notes for the C Programmer
- 10.3 The while Statement
- 10.4 The do-until Statement
- 10.5 The for Statement
  - 10.5.1 Looping Over Structure Elements
- 10.6 The break Statement
- 10.7 The continue Statement
- 10.8 The unwind_protect Statement
- 10.9 The try Statement
- 10.10 Continuation Lines
11 Functions and Scripts
- 11.1 Defining Functions
- 11.2 Multiple Return Values
- 11.3 Variable-length Argument Lists
- 11.4 Ignoring Arguments
- 11.5 Variable-length Return Lists
- 11.6 Returning from a Function
- 11.7 Default Arguments
- 11.8 Function Files
- 11.9 Script Files
- 11.10 Function Handles, Inline Functions, and Anonymous Functions
- 11.11 Commands
- 11.12 Organization of Functions Distributed with Octave
12 Errors and Warnings
- 12.1 Handling Errors
- 12.2 Handling Warnings
  - 12.2.1 Issuing Warnings
  - 12.2.2 Enabling and Disabling Warnings
13 Debugging
- 13.1 Entering Debug Mode
- 13.2 Leaving Debug Mode
- 13.3 Breakpoints
- 13.4 Debug Mode
- 13.5 Call Stack
- 13.6 Profiling
- 13.7 Profiler Example
14 Input and Output
- 14.1 Basic Input and Output
- 14.2 C-Style I/O Functions
15 Plotting
- 15.1 Introduction to Plotting
- 15.2 High-Level Plotting
- 15.3 Graphics Data Structures
- 15.4 Advanced Plotting
16 Matrix Manipulation
- 16.1 Finding Elements and Checking Conditions
- 16.2 Rearranging Matrices
- 16.3 Special Utility Matrices
- 16.4 Famous Matrices
17 Arithmetic
- 17.1 Exponents and Logarithms
- 17.2 Complex Arithmetic
- 17.3 Trigonometry
- 17.4 Sums and Products
- 17.5 Utility Functions
- 17.6 Special Functions
- 17.7 Rational Approximations
- 17.8 Coordinate Transformations
- 17.9 Mathematical Constants
18 Linear Algebra
- 18.1 Techniques Used for Linear Algebra
- 18.2 Basic Matrix Functions
- 18.3 Matrix Factorizations
- 18.4 Functions of a Matrix
- 18.5 Specialized Solvers
19 Vectorization and Faster Code Execution
- 19.1 Basic Vectorization
- 19.2 Broadcasting
  - 19.2.1 Broadcasting and Legacy Code
- 19.3 Function Application
- 19.4 Accumulation
- 19.5 Miscellaneous Techniques
- 19.6 Examples
20 Nonlinear Equations
- 20.1 Solvers
- 20.2 Minimizers
21 Diagonal and Permutation Matrices
- 21.1 Creating and Manipulating Diagonal and Permutation Matrices
- 21.2 Linear Algebra with Diagonal and Permutation Matrices
  - 21.2.1 Expressions Involving Diagonal Matrices
  - 21.2.2 Expressions Involving Permutation Matrices
- 21.3 Functions That Are Aware of These Matrices
  - 21.3.1 Diagonal Matrix Functions
  - 21.3.2 Permutation Matrix Functions
- 21.4 Some Examples of Usage
- 21.5 The Differences in Treatment of Zero Elements
22 Sparse Matrices
- 22.1 The Creation and Manipulation of Sparse Matrices
- 22.2 Linear Algebra on Sparse Matrices
- 22.3 Iterative Techniques applied to sparse matrices
- 22.4 Real Life Example of the use of Sparse Matrices
23 Numerical Integration
- 23.1 Functions of One Variable
- 23.2 Orthogonal Collocation
- 23.3 Functions of Multiple Variables
24 Differential Equations
- 24.1 Ordinary Differential Equations
- 24.2 Differential-Algebraic Equations
25 Optimization
- 25.1 Linear Programming
- 25.2 Quadratic Programming
- 25.3 Nonlinear Programming
- 25.4 Linear Least Squares
26 Statistics
- 26.1 Descriptive Statistics
- 26.2 Basic Statistical Functions
- 26.3 Statistical Plots
- 26.4 Correlation and Regression Analysis
- 26.5 Distributions
- 26.6 Tests
- 26.7 Random Number Generation
27 Sets
- 27.1 Set Operations
28 Polynomial Manipulations
- 28.1 Evaluating Polynomials
- 28.2 Finding Roots
- 28.3 Products of Polynomials
- 28.4 Derivatives / Integrals / Transforms
- 28.5 Polynomial Interpolation
- 28.6 Miscellaneous Functions
29 Interpolation
- 29.1 One-dimensional Interpolation
- 29.2 Multi-dimensional Interpolation
30 Geometry
- 30.1 Delaunay Triangulation
  - 30.1.1 Plotting the Triangulation
  - 30.1.2 Identifying Points in Triangulation
- 30.2 Voronoi Diagrams
- 30.3 Convex Hull
- 30.4 Interpolation on Scattered Data
31 Signal Processing
32 Image Processing
- 32.1 Loading and Saving Images
- 32.2 Displaying Images
- 32.3 Representing Images
- 32.4 Plotting on top of Images
- 32.5 Color Conversion
33 Audio Processing
34 Object Oriented Programming
- 34.1 Creating a Class
- 34.2 Manipulating Classes
- 34.3 Indexing Objects
  - 34.3.1 Defining Indexing And Indexed Assignment
  - 34.3.2 Indexed Assignment Optimization
- 34.4 Overloading Objects
- 34.5 Inheritance and Aggregation
35 GUI Development
- 35.1 I/O Dialogs
- 35.2 Progress Bar
- 35.3 GUI Utility Functions
- 35.4 User-Defined Preferences
36 System Utilities
- 36.1 Timing Utilities
- 36.2 Filesystem Utilities
- 36.3 File Archiving Utilities
- 36.4 Networking Utilities
  - 36.4.1 FTP Objects
  - 36.4.2 URL Manipulation
- 36.5 Controlling Subprocesses
- 36.6 Process, Group, and User IDs
- 36.7 Environment Variables
- 36.8 Current Working Directory
- 36.9 Password Database Functions
- 36.10 Group Database Functions
- 36.11 System Information
- 36.12 Hashing Functions
37 Packages
- 37.1 Installing and Removing Packages
- 37.2 Using Packages
- 37.3 Administrating Packages
- 37.4 Creating Packages
Appendix A Dynamically Linked Functions
- A.1 Oct-Files
- A.2 Mex-Files
- A.3 Standalone Programs
Appendix B Test and Demo Functions
- B.1 Test Functions
- B.2 Demonstration Functions
Appendix C Tips and Standards
- C.1 Writing Clean Octave Programs
- C.2 Tips on Writing Comments
- C.3 Conventional Headers for Octave Functions
- C.4 Tips for Documentation Strings
Appendix D Contributing Guidelines
- D.1 How to Contribute
- D.2 General Guidelines
- D.3 Octave Sources (m-files)
- D.4 C++ Sources
- D.5 Other Sources
Appendix E Obsolete Functions
Appendix F Known Causes of Trouble
- F.1 Actual Bugs We Haven't Fixed Yet
- F.2 Reporting Bugs
- F.3 How To Get Help with Octave
Appendix G Installing Octave
- G.1 Compiling Octave with 64-bit Indexing
- G.2 Installation Problems
Appendix H Emacs Octave Support
- H.1 Installing EOS
- H.2 Using Octave Mode
- H.3 Running Octave from Within Emacs
- H.4 Using the Emacs Info Reader for Octave
Appendix I Grammar and Parser
- I.1 Keywords
- I.2 Parser
Appendix J GNU GENERAL PUBLIC LICENSE
Concept Index
Function Index
Operator Index

GNU Octave

This manual documents how to run, install and port GNU Octave, as well as its new features and incompatibilities, and how to report bugs. It corresponds to GNU Octave version 3.5.91+.

Table of Contents

GNU Octave