title: Drop rows from Dataframe
body: <p>I am attempting to drop rows from my dataframe that do meet a set of conditions. However it doesn't seem to be working.</p>
  <p>Below are the two version which I have tried so far without success:</p>
  <p><strong>Attempt 1</strong></p>
  <pre><code>df = df.drop(df[(df['Factorization'] != 0.5) &amp; (df['Value'] != 30) &amp; (df['Total'] == None)].index)
  </code></pre>
  <p><strong>Attempt 2</strong></p>
  <pre><code>df.drop(df[(df['Factorization'] != 0.5) &amp; (df['Value'] != 20) &amp; (df['Total'] == None)].index, inplace = True)
  </code></pre>
  <p>Please can someone point out where I am going wrong.</p>