title: Get row and column number from Pandas Condition
body: <p>I would like to get the row and column number based on a given condition. The "coordinates" if you will.</p>
  
  <pre><code>import re
  import pandas as pd
  import numpy as np
  dfp = pd.DataFrame({'A' : [1,21,8,44,np.NaN,6,75,8,44,999], 
                      'B' : [1,1,3,5,0,0,np.NaN,9,0,0], 
                      'C' : ['AA1233445','AA1233445', 'rmacy','Idaho Rx','Ab123455','TV192837','RX','Ohio Drugs','RX12345','USA Pharma'], 
                      'D' : [123456,123456,1234567,12345678,12345,12345,12345678,123456789,1234567,np.NaN],
                      'E' : ['Assign','Assign','Hello','Ugly','Appreciate','Undo','Testing','Unicycle','Pharma','Unicorn',]})
  print(dfp)
  
         A    B           C            D           E
  0    1.0  1.0   AA1233445     123456.0      Assign
  1   21.0  1.0   AA1233445     123456.0      Assign
  2    8.0  3.0       rmacy    1234567.0       Hello
  3   44.0  5.0    Idaho Rx   12345678.0        Ugly
  4    NaN  0.0    Ab123455      12345.0  Appreciate
  5    6.0  0.0    TV192837      12345.0        Undo
  6   75.0  NaN          RX   12345678.0     Testing
  7    8.0  9.0  Ohio Drugs  123456789.0    Unicycle
  8   44.0  0.0     RX12345    1234567.0      Pharma
  9  999.0  0.0  USA Pharma          NaN     Unicorn
  </code></pre>
  
  <p>I can get my output by doing:</p>
  
  <pre><code>print(dfp.loc[dfp['B'].isnull()].index.values[0] + 1 ,
  ',', + int([i for i,x in enumerate(dfp.columns.tolist()) if x == 'B'][0] + 1))
  </code></pre>
  
  <p>but the issue is if <code>B</code> had multiple nulls. I would like the coordinates for all nulls.</p>
  
  <p>Is there a way to do this using <code>dataframe.loc</code> or something similar? Adding a 1 to the values is not a big deal, I can do that easily later on.</p>