WM Basic™ User's Manual - Classes

Chapter 1 What is Working Model Basic? 21
WMOutput object
WMConstraint object
WMPoint object
WMInput object
WMBody object
WMDocument object
Most objects in WM Basic are direct equivalents of physical objects in Working Model, and
they feature very similar, if not identical, functionality. For example, most menu commands
are implemented as part of a WMDocument object, which represents a Working Model
document. Likewise, all the entries in Properties, Geometry, and Appearance windows are
available to a WMBody object which represents a body in Working Model.
Properties of an Object
A property describes a state of the object. A WMBody object, for example, has mass as one of
its properties.
To access the information contained in the properties, you need to specify the object name
and add a period (.) followed by the name of the property. For example, if you want to
access the mass property of the WMBody object called Wheel, type:
Wheel.Mass.Value
Most of the properties can be modified as well, for example, in an assignment statement. If
you want to change the mass of the Wheel to 10, simply type:
Wheel.Mass.Value = 10
(The quantity 10 is interpreted in the current unit system.) Note that the result of this
assignment statement is equivalent to that of typing the number "10" in the mass field of the
Properties utility window.
Methods of an Object
Besides having properties, objects also know how to perform certain actions. These actions
are called methods. A WMDocument object, for example, has a method called Run, which runs
the Working Model simulation.
As with properties, if you want to use methods associated with an object, you need to specify
the object and add a period (.), followed by the name of the method. For example, suppose