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<span class="r-in"><span>  <span class="va">X</span> <span class="op">&lt;-</span> <span class="fu"><a href="matrix_.html">matrix_</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/paste.html" class="external-link">paste0</a></span><span class="op">(</span><span class="st">"x_"</span>,<span class="fu"><a href="https://rdrr.io/r/base/c.html