#8203;(int&nbsp;r)</code></th>
<td class="colLast">
<div class="block">Compute the number of non-zero values for the given row,
 which potentially makes a full pass over the underlying row.</div>
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<tr id="i4" class="altColor">
<td class="colFirst"><code>long</code></td>
<th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#countNonZeros(int,int,int,int)">countNonZeros</a></span>&#8203;(int&nbsp;rl,
             int&nbsp;ru,
             int&nbsp;cl,
             int&nbsp;