title: Make a pandas dataframe from a dictionary of lists
body: <p>My question is a bit linked to <a href="https://stackoverflow.com/questions/37934969/creating-a-pandas-dataframe-from-elements-of-a-dictionary">this one</a>, except that I want to turn my lists into rows not columns, and specify the names of the columns.</p>
  
  <p>For example, I start with a dictionary:</p>
  
  <pre><code>my_dict = {'label1' : [0.1, 1.1, 32.1] , 'label2' : [12.3, 5.3, 2.4], 'label3' : [1.5, 7.5, 7.4]}
  </code></pre>
  
  <p>I want to be able to specify column names like:</p>
  
  <pre><code>cols = ['labels','val1' ,'val2, 'val3']
  </code></pre>
  
  <p>and create the dataframe</p>
  
  <pre><code>labels  | val1  | val2  | val3
  label1    0.1     1.1     32.1
  label2    12.3    5.3     2.4
  label3    1.5     7.5     7.4
  </code></pre>