title: Pandas dataframe change all value if greater than 0
body: <p>I have a dataframe</p>
  
  <pre><code>df=
  
  A    B    C
  1    2    55
  0    44    0
  0    0    0
  </code></pre>
  
  <p>and I want to change values to 1 if the value is >0.</p>
  
  <p>Is this the right approach:
  df.loc[df>0,]=1</p>
  
  <pre><code>to give: 
  A    B    C
  1    1    1
  0    1    0
  0    0    0
  </code></pre>