title: Filling a dataframe column based on multiple conditional choices
body: <p>I have a dataframe <code>data</code> which looks like:</p>
  
  <pre><code>Holiday  Report   Action     Power
  0             0        0     1.345
  0             0        0     1.345
  1             0        0     0
  0             0        0     1.345
  0             0        0     1.345
  0             1        0     0
  0             0        0     1.345
  0             1        1     0
  0             0        0     1.345
  0             0        1     0
  </code></pre>
  
  <p>Columns 'Holiday', 'Report' and 'Actions' are pulled in.  Power is calculated by looking a some other columns of data.  I am looking for a line of code that will allow me to set the power to zero if any of the columns 'Holiday', 'Report' or 'Actions' is set to 1.</p>
  
  <p>I can do this procedure one column at a time:</p>
  
  <pre><code>data.loc[staticidx, "power"] = np.where(dayData.Holiday = 1, 0, (a - b)/(c-1))
  data.loc[staticidx, "power"] = np.where(dayData.Report= 1, 0, (a - b)/(c-1))
  data.loc[staticidx, "power"] = np.where(dayData.Actions= 1, 0, (a - b)/(c-1))
  </code></pre>
  
  <p>but is there a way to combine them into one function with something like an OR statement?</p>
  
  <p>Many thanks</p>