import

Import model classes

expand all in page

Parent Section: none (top-level)

Syntax

import namespace_or_class;
import namespace.*;

Description

The import statements allow access to model class or function names defined in other scopes (namespaces) without a fully qualified reference. You must place import statements at the beginning of a Simscape™ file.

There are two types of import statement syntaxes. One is a qualified import, which imports a specific namespace, class, or function:

import namespace_or_class;

The other one is an unqualified import, which imports all subnamespaces, classes, and functions under the specified namespace:

import namespace.*;

The namespace or class name must be a full path name, starting from the library root (the top-level namespace folder name) and containing subnamespace names, as necessary.

Import statements are subject to the following constraints:

  • The imported name must be a full path name, starting from the library root, even if the import statement is used in a component class defined under the same namespace as the domain or component class that is being imported.

  • 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.

  • In qualified import statements, the imported name can refer to a subnamespace, a model class (domain class or component class), or a function. For example, in the import A.B.C; statement, C can be either a subnamespace name, a class name, or a function name. In unqualified import statements, the imported name must refer to a namespace or subnamespace. For example, in the import A.B.*; statement, B must be a subnamespace name (of namespace A).

  • It causes a compilation error if an unqualified imported name is identical to other names within the same scope, provided the duplicate name is in use. For example, assume that subnamespaces A.B and A.B1 both contain a component class C. This code:

    import A.B.C;
import A.B1.*;
component M
   components (ExternalAccess=observe)
     c = C;
   end
end

    causes a compile-time error. However, the following code is legal (provided that D is defined only in A.B) because C is not used:

    import A.B.C;
import A.B1.*;
component M
   components (ExternalAccess=observe)
     d = D;
   end
end

    This code is also legal:

    import A.B;
import A.B1;
component M
   components
     c1 = B.C;
     c2 = B1.C;
   end
 end

    because you import two different names into this scope (B and B1), and access the two different component classes C through their parent classes B and B1.

Examples

expand all

In this example, the composite component consists of three identical resistors connected in parallel.

import foundation.electrical.electrical;  % electrical domain class definition
import foundation.electrical.elements.*;  % all electrical elements
component ParElResistors
  nodes
     p = electrical;
     n = electrical;
  end
  parameters
    p1 = {3 , 'Ohm'};    
  end
  components(ExternalAccess=observe)
    r1 = resistor(R=p1);
    r2 = resistor(R=p1);
    r3 = resistor(R=p1);
  end
  connections
    connect(r1.p, r2.p, r3.p, p);
    connect(r1.n, r2.n, r3.n, n);
  end
end

Version History

Introduced in R2013b

See Also

Topics