Component Equations

Write equations to represent custom component behavior

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.

Sintassi del linguaggio

`assert`	Program customized run-time errors and warnings
`delay`	Return past value of operand
`der`	Return time derivative of operand
`equations`	Define component equations
`function`	Reuse expressions in component equations and in member declarations of domains and components
`integ`	Perform time integration of expression
`intermediates`	Define intermediate terms for use in equations
`tablelookup`	Return value based on interpolating set of data points
`time`	Access global simulation time
`value`	Convert variable or parameter to unitless value with specified unit conversion

Argomenti

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 if statements.
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 tablelookup function in the equations section 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
Use the assert construct 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.