title: extract part of a string in R
body: <p>I wonder if you can help me extract a part of a string using R. I have some column d with the following elements :</p>
  
  <pre><code>d&lt;-
      [1] Homo sapiens (Human)                                                                       
       [2] Pan troglodytes (Chimpanzee)                                                               
       [3] Pan troglodytes (Chimpanzee)                                                               
       [4] Nomascus leucogenys (Northern white-cheeked gibbon) (Hylobates leucogenys)                 
       [5] Macaca fascicularis (Crab-eating macaque) (Cynomolgus monkey)                              
       [6] Macaca mulatta (Rhesus macaque)                                                            
       [7] Macaca mulatta (Rhesus macaque)                                                            
       [8] Callithrix jacchus (White-tufted-ear marmoset)
  </code></pre>
  
  <p>I want to select every thing before the brackets, i.e the answer would be</p>
  
  <pre><code>d&lt;-
      [1] Homo sapiens                                                     
       [2] Pan troglodytes                                                             
       [3] Pan troglodytes                                                              
       [4] Nomascus leucogenys                 
       [5] Macaca fascicularis                           
       [6] Macaca mulatta    
  </code></pre>
  
  <p>Thanks</p>