title: pandas dataframe filter a Object column?
body: <p>I need your lights!
  I have  a dataframe build by this code:</p>
  
  <pre><code>import itertools as ite
  import pandas as pd
  
  items=[1,2,3,4,5,6,7,8,9,10,11,12]
  data = [200,250,190,0,132,149,168,0,198,184,176,203]
  
  result=[(combi,len(da),sum(da),min(da),max(da)) 
          for nbCombi in range(5,10) 
                 for combi,da in zip(ite.combinations(items, nbCombi),ite.combinations(data, nbCombi))]
  
  df=pd.DataFrame(result,columns=["Combinaison","Nb","Poids","Min","Max"])
  df['Ecart']=df['Min']-df['Max']
  </code></pre>
  
  <p>That give me thousands results but one of these ones could be for example:</p>
  
  <pre><code>Combinaison               Nb     Poids     Min     Max    Ecart   
  (1, 2, 5, 6, 10, 11)      6      942        0      250     250
  </code></pre>
  
  <p>The dtypes of the combinaison column is object. Is it an array?</p>
  
  <p>How can I Filter the result in order to exclude the combinations found with the item 1 or 5 for example?
  I know how to filter a dataframe on integer column but I don't know how to do when the type is an array or an object.
  Thank you very much.</p>