title: Pandas: skip lines containing a certain string when reading a file
body: <p>I have a big text file (300000000 rows) but it is full of undesired data, which I would like to remove. Those data are the one containing the string &quot;0000e&quot;.</p>
  <p>I tried:</p>
  <pre><code>f=pd.read_csv('File.txt', skiprows=139, header=None, index_col=False)
  f=f.iloc[:,0]
  f1=f[f.str.contains(&quot;0000e&quot;)==False]
  </code></pre>
  <p>and</p>
  <pre><code>f=pd.read_csv('file.txt', skiprows=139, header=None, index_col=False, chunksize=50)
  dfs = pd.concat([x[x[0].str.endswith('000e')==False] for x in f])
  </code></pre>
  <p>but it is rather long, is there a faster way to skip some lines containing a certain string? Perhaps with na_values?</p>