lass="phrase"><a name="geometry.reference.core.radian.description"></a></span><a class="link" href="radian.html#geometry.reference.core.radian.description">Description</a>
        </h6>
<p>
          Tag defining the unit of plane angle for spherical coordinate systems.
          This tag specifies that coordinates are defined in radians (-PI .. PI).
          It has to be specified for some coordinate systems.
        </p>
<h6>
<a name="geometry.reference.core.radian.h1"></a>
          <span class="phrase"