title: How to skip reading empty files with panda in Python
body: <p>I read all the files in one folder one by one into a DataFrame and then I check them for some conditions. There are few thousand files, and I would love to make pandas raise an Exception when a file is empty, so that my reader funtion would skip this file.</p>
  
  <p>I have something like:</p>
  
  <pre><code>class StructureReader(FileList):
      def __init__(self, dirname, filename):
          self.dirname=dirname
          self.filename=str(self.dirname+"/"+filename)
      def read(self):
          self.data = pd.read_csv(self.filename, header=None, sep = ",")
          if len(self.data)==0:
             raise ValueError
  class Run(object):
      def __init__(self, dirname):
          self.dirname=dirname
          self.file__list=FileList(dirname)
          self.result=Result()
      def run(self):
          for k in self.file__list.file_list[:]:
              self.b=StructureReader(self.dirname, k)
              try:
                  self.b.read()
                  self.b.find_interesting_bonds(self.result)
                  self.b.find_same_direction_chain(self.result)
              except ValueError:
                  pass
  </code></pre>
  
  <p>Regular file that I'm searching for some condition looks like: </p>
  
  <pre><code>"A/C/24","A/G/14","WW_cis",,
  "B/C/24","A/G/15","WW_cis",,
  "C/C/24","A/F/11","WW_cis",,
  "d/C/24","A/G/12","WW_cis",,
  </code></pre>
  
  <p>But somehow I don't ever get <code>ValueError</code> raised, and my functions are searching empty files, which gives me a lot of "Empty DataFrame ..." lines in my results file. How can I make program skip empty files?</p>