A Fan is a derivative from Line. On top of showing the Line, derivative lines are traced representing
Gann Angles.

Screen Shot 2013-11-28 at 8.22.37 PM

Fans angles are fully customizable. See
preferences panel to change preferences.

The initial line, defined by your two clicks, defines the 45 degrees reference.

You can vary the slope of the 45 degree line by selecting (hover over it until it changes color) and, either right clicking (or Option-click) or pressing the space bar, to get the
contextual menu. Within the contextual menu, select Edit Slope.