 a string corresponding to one type of points:
   - marker
   - angle
   - force
   - moment
   - power
   - scalar

  By default an acquisition is set with these units:
   - marker: millimeter (mm)
   - angle: degres (deg)
   - force: newton (N)
   - moment: newton millimeter (Nmm)
   - power: watt (W)
   - scalar: &lt;empty&gt;

  The acquisition is represented by the handle H.  This handle is obtained
  by the use of a btk* function.</pre></div>

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<h2><a name="_cross"></a>CROSS-REF