alguma perda de informa&ccedil;&atilde;o,
</p>
<pre class="example">(%i1) load (descriptive)$
(%i2) load (numericalio)$
(%i3) s3 : read_matrix (file_search (&quot;biomed.data&quot;))$
(%i4) mean (subsample (s3, '(%c[4] # NA and %c[6] # NA), 3, 4, 5, 6));
(%o4) [79.4923076923077, 86.2032967032967, 16.93186813186813, 
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