be grouped into arrays to represent point sets</span>
points = [p1;p2;p3];

<span class="comment">% create a 3D line through 2 points</span>
line12 = createLine3d(p1, p2);

<span class="comment">% an edge is represented by concatenating its vertices</span>
edge13 = [p1 p3];

<span class="comment">% prepare a figure for drawing</span>
figure(1); clf; hold <span class="string">on</span>;
axis <span class="string">equal</span>;
axis([0 100 0 100 0 100]);
set(gcf, <span class="string">'renderer'</span>, <span c