el="anchor" href="#ref-usage"></a></h2>
    <div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">check_covar_balance</span><span class="op">(</span></span>
<span>  <span class="va">w</span>,</span>
<span>  <span class="va">c</span>,</span>
<span>  <span class="va">ci_appr</span>,</span>
<span>  counter_weight <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  covar_bl_method <span class="op">=</span> <span class="st">"absolute"</span>,</span>
<span>  covar_bl_tr