title: All possible combinations of pandas data frame rows
body: <p>I have a pandas data frame having 4 rows:</p>
  
  <p>df:</p>
  
  <pre><code>col1    col2    col3    col4
  A1      A2      A3      A4
  B1      B2      B3      B4 
  C1      C2      C3      C4
  D1      D2      D3      D4
  </code></pre>
  
  <p>How do i find all possible combinations of selecting two rows of this data frame. In this case I can choose 2 rows from 4 rows in 4C2 = 6 possible ways</p>
  
  <p>df1:</p>
  
  <pre><code>col1    col2    col3    col4
  A1      A2      A3      A4
  B1      B2      B3      B4
  </code></pre>
  
  <p>df2:</p>
  
  <pre><code>col1    col2    col3    col4
  A1      A2      A3      A4
  C1      C2      C3      C4
  </code></pre>
  
  <p>df3:</p>
  
  <pre><code>col1    col2    col3    col4
  A1      A2      A3      A4
  D1      D2      D3      D4
  </code></pre>
  
  <p>and so on.....</p>