title: delete line, of a .csv, when certain column has no value python
body: <p>I have a .csv file and I am trying to erase some rows/lines that have no usable information. I want to delete lines that do not have a value in a certain column. I am kinda new to programming and I could not find a way to do this. Is this possible?</p>
  
  <p>I tried to delete a line if it did not have a certain number in it but that did not work as wel.</p>
  
  <pre><code>f = open('C:myfile.csv', 'rb')
  lines = f.readlines()
  f.close()
  
  filename = 'myfile.csv'
  
  f = open(filename, 'wb')
  for line in lines:
      if line != "1":
          f.write(line)
  
  f.close()
  </code></pre>
  
  <p>here are some sample rows:</p>
  
  <pre><code>0,593   0,250984    -20,523384  -25,406271
  0,594   0,250984        
  0,595   0,250984        
  0,596   0,250984        
  0,597   0,250984    -15,793088  -21,286336
  0,598   0,250984        
  0,599   0,908811        
  0,6     0,893612        
  0,601   0,784814    -12,130922  -11,825742
  0,602   0,909238        
  0,603   0,25309     
  0,604   0,38435     
  0,605   0,602954    -8,316167   -3,43328
  0,606   0,642628        
  0,607   0,39201     
  0,608   0,384289        
  0,609   0,251656    -11,825742  -5,874723
  </code></pre>
  
  <p>So I want to delete the rows when there is no number in the third and fourth column. </p>