data.html">breathtest_data</a></code>, even if
only one file was passed. The list can be passed to <code><a href="cleanup_data.html">cleanup_data</a></code>
to extract one concatenated data frame for processing with <code><a href="nls_fit.html">nls_fit</a></code>,
<code><a href="nlme_fit.html">nlme_fit</a></code>, <code><a href="null_fit.html">null_fit</a></code> (no processing) or
<code>stan_fit</code> in separate package <code>breathteststan</code>.</p>
    </div>

    <div class="section level2">
    <h2