r example, a t-test of whether the mean of
the <code>ldl</code> variable is equal to 125 mg/dL can be performed
using <code>rigr</code> as follows:</p>
<div class="sourceCode" id="cb4"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="../reference/ttest.html">ttest</a></span><span class="op">(</span><span class="va">mri</span><span class="op">$</span><span class="va">ldl</span>, null.hypoth <span class="op">=</span> <span class="fl">125</span><span class="op">)</s