Importing Domain and Component Classes
You must store Simscape™ model files (domains and components)
in package directories, as described in Organizing Your Simscape Files.
Like the MATLAB® class system, each package defines a scope (or
namespace). You can uniquely identify a model class name and access
it using a fully qualified reference. For example, you can access
the domain model class electrical
using foundation.electrical.electrical
.
In composite components, class member declarations include user-defined
types, that is, component classes. If you do not use import
statements,
accessing component class names from a different scope always requires
a fully qualified reference. For example, the Foundation library Resistor
block is:
foundation.electrical.elements.resistor
An import mechanism provides a convenient means to accessing classes defined in different scopes, with the following benefits:
Allows access to model class names defined in other scopes without a fully qualified reference
Provides a simple and explicit view of dependencies on other packages
There are two types of syntax for the import
statement.
One is a qualified import, which imports a specific package or class:
import package_or_class;
The other one is an unqualified import, which imports all subpackages and classes under the specified package:
import package.*;
The package or class name must be a full path name starting from the library root (the top-level package directory name) and containing subpackage names as necessary.
You must place import
statements at the beginning of a Simscape file. The scope of imported names is the entire Simscape file, except the setup
section. For
example, if you use the following import
statement:
import foundation.electrical.elements.*;
at the beginning of your component file, you can refer to the Foundation library Resistor block elsewhere in this component file directly by name:
rotorResistor = resistor(R = rotor_resistance);
See the import
reference page
for syntax specifics. For an example of using import
statements in a custom
component, see the Transmission Line example. To view the Simscape file, open the example, then double-click Open the transmission line
component library. In the TransmissionLine_lib window, double-click the T-Section
Transmission Line block and then, in the block dialog box, click Source
code.