sion (knee curve); drc(<var>x</var>,<var>y</var>)=(<var>x</var>)/(<var>y</var>*(<var>x</var>-1)+1); -1&lt;<var>y</var>&lt;1 </dd>
<dt class="col-md-4"> <samp>erf(</samp><var>x</var><samp>)</samp></dt><dd class="col-md-8"> error function</dd>
<dt class="col-md-4"> <samp>exp(</samp><var>x</var><samp>)</samp></dt><dd class="col-md-8"> natural exponential function (<var>e<sup>x</sup></var>)</dd>
<dt class="col-md-4"> <samp>floor(</samp><var>x</var><samp>)</samp></dt><dd class="col-md-8"> largest integral value 