The purpose of the equation section is to establish the mathematical relationships among a component’s variables, parameters, inputs, outputs, time, and the time derivatives of each of these entities. Topics on this page provide detailed information on defining component equations and the related tasks.
|Program customized run-time errors and warnings|
|Return past value of operand|
|Return time derivative of operand|
|Define component equations|
|Reuse expressions in component equations and in member declarations of domains and components|
|Perform time integration of expression|
|Define intermediate terms for use in equations|
|Return value based on interpolating set of data points|
|Access global simulation time|
|Convert variable or parameter to unitless value with specified unit conversion|
- Defining Component Equations
The purpose of the equation section is to establish the mathematical relationships among a component’s variables, parameters, inputs, outputs, time and the time derivatives of each of these entities.
- Simple Algebraic System
This example shows implementation for a simple algebraic system.
- Use Simulation Time in Equations
This example shows how you can access global simulation time from the equation section.
- Using Conditional Expressions in Equations
You can specify conditional equations by using
- Using Intermediate Terms in Equations
Textbooks often define certain equation terms in separate equations, and then substitute these intermediate equations into the main one.
- Using Lookup Tables in Equations
You can use the
tablelookupfunction in the
equationssection of the Simscape™ file to interpolate input values based on a set of data points in a one-dimensional, two-dimensional, or three-dimensional table.
- Programming Run-Time Errors and Warnings
assertconstruct to implement run-time error and warning messages for a custom block.
- Initial Equations
Specify additional equations to be executed during model initialization only.
- Simscape Functions
Use Simscape functions to reuse expressions in equations and member declarations of multiple components.
- Import Symbolic Math Toolbox Equations
Example of using Symbolic Math Toolbox™ software to solve the physical equations, generate code in the format appropriate for the Simscape language equation section, and incorporate the generated code into the equation section of a component file.