title: Standard deviation of time series
body: <p>I wanted to calculate the mean and standard deviation of a sample. The sample is two columns, first is a time and second column, separated by space is value. I don't know how to calculate mean and standard deviation of the second column of vales using python, maybe scipy? I want to use that method for large sets of data.
  I also want to check which number of a set is seven times higher than standard deviation.
  Thanks for help.</p>
  
  <pre><code>time value
   1 1.17e-5
   2 1.27e-5
   3 1.35e-5
   4 1.53e-5
   5 1.77e-5
  </code></pre>
  
  <p>The mean is <code>1.418e-5</code> and the standard deviation is <code>2.369-6</code>.</p>