='output co'>#&gt; [1] "This is a strange string" "And this another one"    
#&gt; [3] NA                        </div><div class='input'><span class='fu'>to_random_case</span>(<span class='no'>strings</span>)</div><div class='output co'>#&gt; [1] "THiS iS A sTRANgE_stRInG" "ANd thIS anOThER_OnE"    
#&gt; [3] "NA"                      </div><div class='input'><span class='fu'>to_title_case</span>(<span class='no'>strings</span>)</div><div class='output co'>#&gt; [1] "This is a Strange String" "And this Ano