title: Get index number when condition is true in 3 columns
body: <p>I've a question regarding some code in python. I'm trying to extract the index of the first row when the condition TRUE is satisfied in 3 different columns. This is the data I'm using:</p>
  
  <pre><code>       0       1       2             3           4
  0   TRUE    TRUE    TRUE    0.41871395  0.492517879
  1   TRUE    TRUE    TRUE    0.409863582 0.519425031
  2   TRUE    TRUE    TRUE    0.390077415 0.593127232
  3   FALSE   FALSE   FALSE   0.372020631 0.704367199
  4   FALSE   FALSE   FALSE   0.373546556 0.810876797
  5   FALSE   FALSE   FALSE   0.398876919 0.86855678
  6   FALSE   FALSE   FALSE   0.432142094 0.875576037
  7   FALSE   FALSE   FALSE   0.454115421 0.863063448
  8   FALSE   TRUE    FALSE   0.460676901 0.855739006
  9   FALSE   TRUE    FALSE   0.458693197 0.855128636
  10  FALSE   FALSE   FALSE   0.459201839 0.856451104
  11  FALSE   FALSE   FALSE   0.458693197 0.855739006
  12  FALSE   FALSE   FALSE   0.458082827 0.856349376
  13  FALSE   FALSE   FALSE   0.456556902 0.856959746
  14  TRUE    TRUE    TRUE    0.455946532 0.858180486
  15  TRUE    TRUE    TRUE    0.455030976 0.858790857
  16  TRUE    TRUE    TRUE    0.454725791 0.858485672
  17  FALSE   FALSE   FALSE   0.454420606 0.857875301
  18  FALSE   FALSE   FALSE   0.454725791 0.858383943
  19  FALSE   TRUE    FALSE   0.453199866 0.856654561
  20  FALSE   FALSE   FALSE   0.451979125 0.856349376
  21  FALSE   FALSE   FALSE   0.45167394  0.856959746
  22  FALSE   FALSE   FALSE   0.451775669 0.857570116
  23  FALSE   FALSE   FALSE   0.45106357  0.857264931
  24  TRUE    TRUE    TRUE    0.450758385 0.856654561
  25  TRUE    TRUE    TRUE    0.4504532   0.856044191
  26  TRUE    TRUE    TRUE    0.449232459 0.856349376
  27  TRUE    TRUE    TRUE    0.448316904 0.855535549
  </code></pre>
  
  <p>and I need to get the index number only when there are 3 'True' conditions:</p>
  
  <pre><code>0   
  14  
  24
  </code></pre>
  
  <p>Thank you!</p>