r">Anirban Chetia</h4>
            
            <h4 class="date">2020-07-20</h4>
      
      
      <div class="hidden name"><code>substring_and_gregexpr.Rmd</code></div>

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<li>The functions <code><a href="https://rdrr.io/r/base/substr.html">substring()</a></code> and <code><a href="https://rdrr.io/r/base/grep.html">gregexpr()</a></code> (<code>perl = TRUE</code> var