title: Python - how to convert a list to log(list)
body: <p>I have a list of values and would like to convert it to the log of that list or pass the log of a list to a function.  I'm more familiar with R and you can usually throw some () around anything.  When I attempt this in Python I get the error:</p>
  
  <pre><code>TypeError: must be real number, not list
  </code></pre>
  
  <p>List looks like this:</p>
  
  <pre><code>pressures[:5]
  Out[11]: [1009.58, 1009.58, 1009.55, 1009.58, 1009.65]
  </code></pre>
  
  <p>It doesn't really matter where I try to take the log, I get the same error...in a function:</p>
  
  <pre><code>plt.plot(timestamps, log(pressures))
  plt.xlabel('Timestamps')
  plt.ylabel('Air Pressure')
  plt.show()
  </code></pre>
  
  <p>Whilst parsing data:</p>
  
  <pre><code>pressures = log([record['air_pressure'] for record in data])
  </code></pre>