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            <h2><font color="#FFFFFF">Edge Orientation Shortcuts</font></h2>
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<p>When editing graphs, there are some shortcuts available to make reorienting edges a little easier. For directed
    acyclic graphs (DAGs), you can change the orientation of an edge by clicking on the tail of the edge; when you do
    this, the tail will become the head, and vice-versa. For example, in this graph, </p>
<p><img src="../images/edge_orientation_shortcuts1.gif" width="576" height="549"></p>
<p>if you click on the tail of the edge X1--&gt;X2, that edge will reverse direction:</p>
<p><img src="../images/edge_orientation_shortcuts2.gif" width="575" height="549"></p>
<p>You can switch it back the other way by clicking on the endpoint near X2; in that case, it will have the orientation
    of the the original edge once again.</p>
<p>In general, clicking on an endpoint of any edge in a graph will orient that edge as a directed edge in the direction
    of the endpoint you clicked on. This makes turning, e.g., CPDAGs into DAGs easy. </p>
<p>In graphs that support more types of endpoints, holding down the shift key and clicking on an endpoint cycles that
    endpoint between the three possible endpoints of a general graph: null (-), arrow (-&gt;), and circle (-o). So, for
    instance, if you copy the above graph into a General Graph model and the click on the endpoint of the edge X1&lt;--X2
    near X1, it will first turn into a null endpoint:</p>
<p><img src="../images/edge_orientation_shortcuts3.gif" width="600" height="585"></p>
<p>then it will turn into a circle endpoint:</p>
<p><img src="../images/edge_orientation_shortcuts4.gif" width="599" height="590"></p>
<p>and then, if you click one more time, it will turn back into an arrow endpoint:</p>
<p><img src="../images/edge_orientation_shortcuts2.gif" width="575" height="549"></p>
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