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Reference Guides
Explore the Extended Definitions, OML Guides, Block Library, API Guide and Glossary.
Scripting Guide for OpenMatrix Language
OpenMatrix is a mathematical scripting language.
Operator Descriptions (tables)
Each operator in this section is explained with the operations of scalars, vectors, and matrices that are allowed for said operator.
Matrix Multiplication
Matrix Multiplication is defined as the multiplication of two matrices.

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Reference Guides
Explore the Extended Definitions, OML Guides, Block Library, API Guide and Glossary.
- Extended Definitions for Advanced Users
  PDF file with in-depth information on key topics in the User's Guide.
- Scripting Guide for OpenMatrix Language
  OpenMatrix is a mathematical scripting language.
  - Literals
    Literals are items that are constant throughout the life of the application. Literals include numeric, imaginary, characters, strings, logicals, and Other (NaN/Inf).
  - Data Types
    Data types are items that are constant throughout the life of the application and are built into the OpenMatrix language.
  - Strings
    Strings are arrays of characters.
  - Variables and Assignments
    OML language scripts manipulate data through variables. Variables are referred to by their name (alphanumeric) and can be created (assigned) and deleted as described in this section.
  - Indexing
    Indexing is used to retrieve one or more specific values out of a collection.
  - Operators
    Operators are used to combine operands.
  - Operator Descriptions (tables)
    Each operator in this section is explained with the operations of scalars, vectors, and matrices that are allowed for said operator.
    - Addition
      The table below describes the Addition operator.
    - Colon
      The colon operator has a number before and after it.
    - Complex Transpose
      Complex Transpose is different from transpose in that any complex numbers are also conjugated.
    - Inequality Operators
      All inequality operators return logical values (either 0/false or 1/true).
    - Left Division
      This type of division is different from Left Matrix Division in that the division is performed on each pair of corresponding elements.
    - Left Matrix Division
      Left Matrix Division (A\B) is defined as solving the equation Ax = B.
    - Logical Operators (tables)
      All inequality operators return logical values (either 0/false or 1/true).
    - Matrix Multiplication
      Matrix Multiplication is defined as the multiplication of two matrices.
    - Matrix Power
      Power means multiplying something by itself a specific number of times. Likewise for matrix power.
    - Multiplication
      This type of multiplication is different from Matrix Multiplication in that the multiplication is performed on each pair of corresponding elements.
    - Power
      This type of power is different from Matrix Power in that the power (multiplication of something by itself) is done through each corresponding element.
    - Right Division
      This type of division is different from Right Matrix Division in that the division is performed on each pair of corresponding elements.
    - Right Matrix Division
      Right Matrix Division (B/A) is defined as solving the equation xA = B.
    - Short Circuit
      Short Circuit includes && (short circuit and) and || (short circuit or). They are both logical operators.
    - Subtraction
      The table below describes the Subtraction operator.
    - Transpose
      The transpose of a matrix is also a matrix. The rows of the transpose are the columns of the original matrix and vice-versa.
  - Expressions and Statements
    Statements are made of expressions, which may be simple or complex.
  - Flow of Control and Looping
    Loops are used to perform the same set of statements multiple times.
  - Workspace and Scoping Rules
    There are two types of workspaces: Local and Global.
  - Functions
    Functions are packets of statements that can be used repeatedly.
  - Scripts and Functions
    OpenMatrix statements persist in .oml files.
  - Files
    This section describes files that can be manipulated by the OpenMatrix Language.
  - Error and Warning Messages
    Errors and warning messages are both output in the console (or the Command Window in GUI mode) of Twin Activate.
  - Plotting and Visualization
    Create 2D and 3D plots and control their style and appearance.
  - Objects in OpenMatrix Language
    Objects in OML are defined using the classdef keyword. This creates a blueprint for an object but does not actually create (instantiate) anything.
- Reference Guide for OpenMatrix Language Functions
  The Reference Guide contains documentation for all functions supported in the OpenMatrix language.
- Block Reference Guide
  Describes all of the blocks in the installed Twin Activate library.
- Function Guide for Twin Activate
  Provides information about developing and simulating models through the Twin Activate Application Program Interface.
- Glossary
  Key terms associated with the software.
Frequently Asked Questions
You've got questions? We've got answers!

Matrix Multiplication

Matrix Multiplication is defined as the multiplication of two matrices.

It requires the number of columns in the first matrix to equal the number of rows in the second matrix. The resulting matrix will have the same number of rows as the first matrix, and the same number of columns as the second matrix.

Table 1.
*	Scalar	Row Vector	Column Vector	Matrix
Scalar	Multiplies the two scalar values.	Multiplies the scalar with each element in the row vector.	Multiplies the scalar with each element in the column vector.	Multiplies the scalar with each element in the matrix.
Row Vector	Multiplies the scalar with each element in the column vector.		Use matrix multiplication.	Use matrix multiplication.
Column Vector	Multiplies the scalar with each element in the column vector.	Use matrix multiplication.		Use matrix multiplication.
Matrix	Multiplies the scalar with each element in the matrix.	Use matrix multiplication.	Use matrix multiplication.	Use matrix multiplication.

Examples

3 * 3
ans = 9 

[1 5 4] * [3; 5; 7]
ans = 56
  
[3 4; 5 8] * [4; 7]
ans = [40 ; 76]

Invalid examples:

[3 5 4] * [3 6 7]
[3 4] * [1 4;3 6; 10 2]