1  <?xml version="1.0" standalone="no"?>
 2  <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG April 1999//EN" "http://www.w3.org/Graphics/SVG/svg-19990412.dtd">
 3  <svg width="4in" height="3in">
 4    <defs>
 5      <symbol id="Triangle" min-x="0" min-y="0" max-x="100" max-y="100" ref-x="0" ref-y="50">
 6        <path d="M 0 0 L 0 100 L 100 50 z"/>
 7      </symbol>
 8    </defs>
 9    <desc>An double-headed arrow example using markers
10    </desc>
11    <path d="M0 0">
12  <!-- Place an arrowhead rotated 180 degrees at the 
13           beginning of the path -->
14      <marker href="#Triangle" width="200" height="200" style="text-transform: rotate(180)"/>
15      <data d="M 2000 2000"/>
16  <!-- Turn off markers in the middle of the path -->
17      <marker href=""/>
18      <data d="L 4000 2000 L 4000 4000"/>
19  <!-- Place an arrowhead at the end of the path-->
20      <marker href="#Triangle" width="200" height="200"/>
21      <data d="L 6000 4000"/>
22    </path>
23  </svg>