2.2.2 Vectors

The basic geometric entity specifying direction is the vector object. Vector objects reference the direction of a 2D or 3D vector, in global coordinates or in local coordinates on a specified body. Vector objects may be given as 2D or 3D vectors in global coordinates, or they may have the head Vector and be given in local coordinates on a specific body.
A Line can be used to specify a vector object, in which case the direction of the Line is used as the direction of the vector. A Plane (3D only) may also be used to specify a vector object, in which case the normal direction of the Plane is used as the direction of the vector. See the following two subsections for further information on Line and Plane.
Any Mech function that calls for a vector object accepts either of the following syntax.

2D

Methods of defining 2D vector objects.

3D

Methods of defining 3D vector objects.

Assuming that the appropriate body object definition has been made, any vector on any body can be referenced through either its global coordinates, its local coordinates, or its local point number. The following example shows several vector objects that are functionally identical.

This defines some coordinates on the crank.

In[7]:=

Here are two identical vector specifications.

In[9]:=