VFGEN is a command-line program. The first argument to the command determines the format of the output that is generated. A typical invocation of VFGEN looks like
The menu on the left provides links to the various section of the User's Guide. The menu entry labeled "Vector Field File" links to the description of the vector field file used by VFGEN to define a vector field. The remaining menu entries below "User's Guide" are all the VFGEN commands. The documentation for each command includes examples of its use.